m KXjOC SCIENCE mooGCR ■OCMjOvTC f Jl Tf iifrfTiTi HfluuQQ GOSSIP. HARDWI CKE'S SCI ENCE-GOSSI P: 1888. HARDWICKE'S 4ip4£=©rr?SM£: AN ILLUSTRATED MEDIUM OF INTERCHANGE AND GOSSIP FOR STUDENTS AND LOVERS OF NATURE. EDITED BY Dr. J. E. TAYLOR, F.L.S., F.G.S., F.R.G.S.I., HON. MEMBER OF THE MANCHESTER LITERARY CLUB, OF THE NORWICH GEOLOGICAL SOCIETY, OF THE MARYPORT SCIENTIFIC SOCIETY, OF THE ROTHERHAM LITERARY AND SCIENTIFIC SOCIETY, OF THE NORWICH SCIENCE-GOSSIP CLUB, OF THE GEOLOGICAL SOCIETY OF AUSTRALASIA, OF THE VICTORIAN FIELD NATURALISTS' CLUB, ETC. ETC. VOLUME XXIV Uon&on : CHATTO AND WINDUS, PICCADILLY. 1888. [All rights reserved.) LONDON : PRINTED BY WILLIAM CLOWES AND SONS, LIMITED, STAMFORD STREET AND CHARING CROSS. 10 L> 0 lJ~ PREFACE. TWENTY-FOUR years have elapsed since this Magazine was founded by the genial publisher whose name it still bears. It is a long life for so popular a serial as SCIENCE-GOSSIP, but has there been any flagging in its vitality ? Many -honoured names, both in amateur and professional science, have helped to build up its world- wide reputation. It has been the ladder by which many dis- tinguished men have climbed to fame. Scores of others who have helped our Magazine have passed away. Though they rest from their labours, their works follow them ; and not a few of their articles are sought out in back volumes for the wisdom and experience they generously placed at the service of the public, and especially at that of the young naturalists who were to succeed them. In spite of the little bickerings and breezes we experience, even in scientific circles — the accumulated heritage from ancestors who knew not science — is there a single profession or calling in which men are so willing to help each other as in natural science ? Our columns bear evidence to the prompt readiness with which young beginners, and even more advanced students, obtain assistance as soon as they ask for it. The spheres of science are ever widening, like those of a disturbed lake. There is little fear the function of Science-Gossip will die out for lack of fresh information. Every new discovery opens out fresh vistas, and calls forth additional comment and criticism. We claim that, from the popular point of view, our twenty-four volumes give as complete and even a more continuous History of recent Science than can be found anywhere else. Our severest critics will admit that the present Volume is in no wise inferior in variety, interest, and PREFACE, information to its predecessors. Our generous contributors of articles are quite as enthusiastic as their forbears. The increased demand on our " Exchange Columns " is a good indication of the rapidity with which Natural History has spread. That term is now more comprehensive than ever. It embraces sections and sub-sections of research which, a quarter of a century ago, were hardly thought of. Now, every one of them is engaging the attention of men and women, and sweetening their lives, as the eager interest shown for Collecting manifests. We would do more if we could. The low price of SciENCE- GOSSIP makes it imperative that its circulation shall be increased, so as to enable Editor and Publisher to carry out their desires. Every reader can assist us by joining our enthusiastic corps of " recruiting sergeants," and getting another enlisted in our large ranks of Subscribers. An increase of another five thousand per month in our circulation would strengthen our hands for good. We thank kind friends all round (and there is not a part of the globe where our Magazine has not friends) for help, sympathy — even criticism. The Preface enables the Editor once more figuratively to shake hands with all, and to wish them a Happy New Year ! * LIST OF ILLUSTRATIONS. Ai.der, Stem of Common, showing Bulges caused by Woodbine, 275 Anterior Antennae, 32 Anvil Clouds, 5 Asplanchna myrmclco, \tz Bass [Labrax lupus), 61 Branch of Manihot utilissima, 84 Branch of Piper mctliysticam, 85 Catching Turtles, 104 Cavity of Scale of Toothwort, 13 Cavity of Young Scale, with Spores, of Toothwort, 13 Centipedes, Group of, 272 Cocoon of Argyroneta aqnatica, 227 Common Flying-Fish, 244 Cristatella mucedo, 108 Dactylopterus volitans, 244 Development within the Egg of the Gnat [Tipula plumosa), 132, 133 Diagrammatical Figure of Young Larva {Tipida plumosa), 156 Diagram of Light reflected by Green Leaves, 8 Diagram of Light reflected from Green Pigment, 8 Diagram of Three Primary Colour Sensa- tions, 29 Digestive System of Tipula plumosa, 156 Ecdysis of Pediculus capitis, 220 Ertemias tetrathrix, 28 Extension Diagram, showing the Position of the Muscles of the Body of Tipula plumosa, 157 External and Internal Terminal Claws of Phthirius inguinalis, 1S1 Female of Watek-Spider, 227 Floscularia aunulata, 9 Flower of Garcinia mangostana, 197 Flower Spike, 13 Fossil Freshwater Shells, 57 b'redericella sultana, 108, 109 Front View of Daphnia, 36 Fruit of Garcinia, 197 Gcophilus electricus, 273 Gonium pectorale, 248 Head of Bass, 61 Head of Male Tipula plumosa, 150 Head of Vinegar Eel, 52 Imago, 160 jf/tlus tcrrcstris, 273 Larch, having Six Aftergrowths, 205 Larch, showing Natural Engrafting, 204 Lathyrus tuhcrosus, 225 Lichomolpus sabellce, 32 Longitudinal Section of Fully-developed Scales, showing the Connection of the Small Cavities with one another in Toothwort, 13 Longitudinal Section of Scale of Tooth- wort, 12 Male of Asplanchna myrmeleo, 156 Male of Water-Spider, 227 Marigold, 148 Mature Female, 52 Melon Seedling, 165 Middle and Posterior Parts of Balauo- glossus saruiensis, 124 Nervous System of Tipula plumosa, Nymph, 150 Ovum of Phthirius inguinalis, 181 Pair of Swimming Feet, 32 Part-Section of complete Flower, the Marigold, 148 Posterior Antennae of Lichomolpus sa- bclhe, 32 Probosc's as disrupted from Body, 101 Proboscis exserted, 100 Reproductive Organs of Female [An- guillula aceti), 53 Section at St. Ekth, 129 Side View of Daphnia, 36 Spider, Natural Size, 159 Spider with Parasite, 159 Stomata and Glandular Hairs in Cavity of Scale of Toothwort, 13 Terminal Claw of Second Pair of Legs of Phthirius inguinalis, 182 Transverse Section of a Fully-developed Scale of Toothwort, 12 Transverse Section of Underground Stein near the Base of Toothwort, 13 Tree-Stem, showing direction taken by Ivy Stems and Branches, 275 Trifolhun stcllatum, 149 vorticella, 252 Wing of Termite, 229 Vorm, as usually seen crawling, 100 Worm under Compression, 100 Young Anguillula escaping, 53 SECTION-CUTTING APPLIED TO INSECTS. By H. M. J. UNDERIIILL. 4.ITHIN the last few years the art of section-cutting has been greatly im- proved, but ac- counts of the methods in use have as yet hardly found their way into ordinary mi- croscopic hand- books, and to the amateur, who mo- destly restricts his dissections to in- sects, they are, I believe, almost un- know n. The general principles of the methods are in all cases the same, but the application of them to various sorts of tissues is frequently different ; so, in working out the details for insects, although I write chiefly for the amateur, I may possibly contribute something of use to the student. Most microscopists find that a great deal of the interest of their microscopy lies in preparing speci- mens. If there be any one of these who has never tried section-cutting, let him buy a microtome and set to work at once. It is quite a fascinating amuse- ment, a kind of refined " whittling a stick " — that pleasure so dear to youth. After a few remarks on microtomes, I propose to divide my observations into four parts ; Preparing the specimens ; cutting, mounting, and staining them. I would premise that, if I recommend a process for insects, it does not follow that it will do for anything else. The most important thing in getting perfect sections is the proper preparation of the insect, previous to cutting it. If an object be well prepared, No. 277.— January 1888. good sections may be obtained with the commonest of microtomes ; of course, the better the microtome, the better the sections : yet the best of microtomes is useless, if the specimens be not rightly prepared. Section machines seem to vary in price from 8s. to j£8. As far as I know, the cheapest are practically as good as those of medium price, for when cutting is effected by holding the razor in the hand, one can never be sure to the 355th of an inch where its edge will come, in consequence of the elasticity of the steel. This is the arrangement in all the moderate priced instruments I have seen, so that a £2 machine is not essentially better than an 8s. one. In the more expensive forms this uncertainty is eliminated by the motion of the razor (or object) being effected mechani- cally. The best of these is said to be the Cambridge "Rocking Microtome," price ^5 $s. I have got very good sections with a section machine of the cheapest kind, and I have seen most excellent vege- table sections which were cut without a microtome at all. So the student need not lay aside section- cutting for lack of an expensive machine. A good razor, however, is a necessity. Preparing Specimens. A great many fluids have been compounded for hardening tissues previous to cutting them. Some do very well for insects, but any which contain chromic acid are totally destructive. This reagent renders chitine extremely friable, and in fact, makes the whole section so brittle, that it is ihardly possible to mount it unbroken. Moreover, in spite of all said to the contrary, it prevents proper staining. But the fluid readiest to hand is common methylated spirits, and this answers every purpose. Soak the insects in it for a week or two, or as much longer as you like. Soft bodied insects may shrink if put into methylated spirits at once. A day's previous soaking in dilute picro-sulphuric acid solution will prevent this. Then let them have three or four days in absolute alcohol, changing the alcohol once. Transfer them to oil of HARD WICKE'S SCIENCE- G OSSIP. cloves, in which let them stay for a day ; and, after the oil of cloves, let them be in turpentine another day. For some reason that I do not understand, soaking first in oil of cloves and then in turpentine prevents tissues from shrinking when they are put into wax. If oil of cloves, turpentine, or chloroform be used alone, shrinking can hardly be avoided. For this " wrinkle " I am indebted to Dr. Schonland, of the Botanic Gardens, Oxford. Now melt some paraffin wax before a gas-stove or over a water bath. Be very careful to have it only just above its melting-point. Warm the bottle of turpentine containing the specimens, pick them out, and drop them into the melted wax. This must be maintained at the same temperature for about ten hours. Great care must be taken not to let it get too hot, or the insects will shrink. If you put the speci- mens in at night, they will be ready by morning. By this time the wax should have penetrated every part of the insect, and the excellence of the sections depends upon this being done completely. No perfection of microtome will compensate for imper- fectly imbedded specimens ; but, as I have said, you can cut good sections of a well-imbedded insect in a common machine. This method of imbedding answers for most insects, but very soft ones need yet more care to avoid shrinkage. Either of the two following methods will do. Put the insects into a small open vessel with enough turpentine to cover them, add a good many chips of wax. Or this : melt some wax in the vessel and let it get cold ; put the insects with enough turpentine to cover them on the top of this. Then (in either case) gradually bring the wax to the melting-point before the stove or in a hot- air box, and keep it just melted for hours until the turpentine is all evaporated. The penetration of the wax is so gradual, that there is no danger of the insect shrinking. The vessel in which the wax is allowed to get cold must be flat bottomed ; and the objects should be arranged in it at intervals in such positions that the bottom of the vessel is at right angles to the plane of the sections which you intend to cut. When the wax is quite hard, the specimens may be carefully cut out in little cubes of wax, and kept for any length of time until wanted. The wax used must be pure paraffin. I have tried all sorts of mixtures and different waxes, but nothing does so well as pure paraffin. It is of great import- ance to have it of the right melting-point. The Cambridge people say that with their microtome this does not matter, but my experience with the machine is different. If the temperature of your room be 560 to 6o° Fahr., the proper melting-point of the wax is no°. You should have a thermometer, and, when- ever you want to cut sections, you must bring the temperature to this point. In summer, when you cannot cool the air to 6o°, you must use harder wax, preserving the difference of 500 between the tempera- ture of the room and the melting-point of the wax.. The reason for this particularity is that, if the wax be too hard, the sections will curl up as you cut them, and frequently break. On the other hand, if it be too soft, it gives way under the pressure of the razor. Any grocer will get you paraffin through Price's (or some other) candle company. It is made of four degrees of hardness, melting at uo°, 1150, 1200, ami 1250. The probable price will be 6d. per pound. Cutting the Sections. If you have a microtome of the common sort, with a well, fill the well with melted wax, and let it get quite cold. Then screw it up until about half an-inch of wax appears above the cutting plate of the instru- ment. Remove this with the razor, and if the block of wax seem at all loose in the well, thrust a thin splinter of lucifer match between the wax and the side of the well. Take now one of the cubes of wax containing an insect to be cut ; square it roughly with a pen-knife ; fasten it to the wax in the well by means of the heated blade of an old knife. When it is cold and hard again, finish off the squaring process- accurately, taking care that the opposite sides are- parallel. Screw down the machine until the top of the little cube is level with the surface of the cutting plate, and the specimen is ready for cutting. Take off a few preliminary slices, and when you have cut down to the object, place the razor with its edge parallel to and almost touching one of the sides of the cube. Draw it sharply towards you without any motion sideways, but in a direction exactly at right angles to that side of the block with which its edec- is parallel. Let the section remain on the razor blade, and after again turning up the screw of the- microtome, repeat the cut, using exactly the same- portion of the razor edge to cut with by placing the- section already cut precisely behind the little squire block of wax. The new section will stick to the edge of the first one and push it across the razor blade. The same process, indefinitely repeated, will produce a ribbon of sections almost as neatly as a rocking microtome will do it. Success depends on the melt- ing-point of the wax, and the temperature of the room, being properly adjusted, as before explained. After a little practice, I could readily get unbroken- ribbons of 20 to 40 sections. After this, they became too long to be manageable. The advantages of ribbons over single sections I consider to be two : — they are much easier to manipulate ; and they facilitate getting a series of sections in their proper- order. This is an important point when you arc cutting up an insect. Besides, having all the sections cut before any are put upon the slide, you are able to count them, and so calculate the space they will occupy. You can, therefore, arrange them with proper regard to the middle of the slide — a great thine; to all who love neatness. HARD WICKE' S SCIENCE- G OS SIP. Mounting. In the ordinary way of mounting sections, they are loose, and must be transferred with a " section lifter" of some kind from fluid to fluid, "as they are washed and stained. This is very troublesome and risky with any sections, and impossible with insects, because they always break up. The safe way, and at the same time the way which produces the best results and is also the least trouble, is to fasten them to the slide as soon as they are cut, and then there is no risk of breaking them. This is done by brush- ing the face of the slide with a mixture of four or five parts oil of cloves to one part collodion, spreading it thinly and evenly, and covering a little larger space than the section will occupy. Some people prefer glycerine and white of egg, spread very thinly. I lay my slides on a card, the size of a slide, ruled in the middle into squares T\, of an inch in diameter. Take up a length of ribbon by placing the blade of a scalpel underneath it, and, guided by the card, put the end section down at the right place on the slide, gently draw away the scalpel, and flatten down the ribbon on to the slide with the back of the blade. See that every part of every section touches the glass and is held by the cement. When all the sections are arranged, take hold of one end of the slide with a clip, and hold it over a flame for a few moments until the wax is melted. The melted wax and the oil of cloves draw away from the sections and form a ring of drops round them. These should be wiped off, because they take the colour when the slide is stained. Plunge the slide into turpentine. A few seconds suffice to dissolve the wax and oil of ■cloves, and the sections remain on the slide, held fast by the collodion. If staining be unnecessary, or if the object has been stained whole, the turpentine should be washed off with benzine, and the slide mounted in balsam thinned with benzine. If the objects are to be stained on the slide — and this method, I think, gives the best results — proceed as follows. Remove the slide from the turpentine, and wipe off as much of it as possible ; pour a few drops •of absolute alcohol on the sections ; and, when this has dissolved out the turpentine, put the slide into methylated spirits. It is best to let it soak in this for a quarter of an hour at any rate, in order to extract all the turpentine. Transfer it to clean water, and soak it in that another ten minutes or so. Now stain, leaving it as long as is necessary in the colour. But, if you wish to remove pigment to show the structure of eyes or other pigmented parts, the slide must be left in eau dejavelle until all the pigment is dissolved, and then well washed in water, before being stained. The time needed for staining is generally fifteen minutes, but the slide should be examined frequently to see how it is getting on. The sections must not be overstained if hematoxylin .be used ; for, although overstain can be washed out with acidulated spirit, or aqueous alum solution, the sharpness of outline given by the colour is decidedly impaired. After staining, the slides must be brought back to balsam by a reverse process ; viz., by passing them through (i) water ; (2) methylated spirits; (3) absolute alcohol ; (4) benzine ; (5) mount in balsam and benzine. Turpentine and oil of cloves should not be used for No. 4 (benzine), because they cause many colours to fade, which benzine will fix. Glycerine is not a good mounting medium, for my experience of it is that all stains fade in it. All these directions may sound very complicated to the tyro, but the method of mounting is really very easy, because the sections are fixed to the slide. There is, therefore, no danger of their floating away when the cover is let down on them, and no trouble with air-bubbles. Staining. A few words on staining may be useful. As I have already said, specimens may be stained whole, before they are imbedded in wax, or stained on the slide after they are cut. Some like one way, some the other. I find it difficult to stain the object whole to just the right tinge of colour ; I either get it too dark or only partially stained, and it is specially difficult with insects because of their impervious shells. If you make holes in them with needles, you damage the internal anatomy. Therefore, I prefer staining the sections on the slide, in the way that I have described. All sorts of colours have been recommended. Aniline dyes are in great favour with some people, and very nice double stains of vegetable sections may be made with them. Borax, carmine, and picro-carmine are much used. These colours are much better than aniline dyes, in that they stain less diffusely and more " selectively," as it is called. But I reject them, because with any objective higher than a quarter-inch, they give no sharpness of out- line. I use hematoxylin, and hematoxylin would be the perfection of stains, if — it is a great pity, that "if!" — it did not labour under the suspicion that it fades in a year or two. That it fades sometimes there is no doubt ; but it is doubtful if the fading be due to the fault of the colour, or to the reagents used in preparing the specimen. It certainly fades if the specimens have been hardened in chromic acid, or any chromate ; and I know that turpentine causes it to fade. I have great hopes, however, that, when the specimens have been hardened in simple spirit, washed finally with benzine, and mounted in balsam and benzine, the colour will keep. Some slides that I mounted six months ago in this way show no sign of turning colour as yet ; but six months, of course, is a test not long enough. A friend of mine, who is very skilful in mounting, says that he considers the cause of the fading of B 2 HA RD WICK& S SCTENCE- G OS SIP. hematoxylin to be, not in any reagents used in preparing the specimens, but in the presence of tannin in the ordinary hematoxylin stains. His recipe for preparing the stain so as to get rid of the tannin may be found in the " Quarterly Journal of Microscopical Science," 1S85, at the end of an article on the " Eyes of Insects." Perhaps tannin, chromates, acids, and turpentine all contribute to make it fade. My own recipe is as follows ; it gives as good results as any hematoxylin 1 have ever seen ; but if fading be because of the presence of the tannin in the logwood, my slides will fade in time. Crush ordinary extract of logwood to powder, and dissolve a saltspoonful of it in hot water ; add about 2 oz. of methylated spirit ; dissolve a teaspoonful of alum in some more hot water, and mix the two solutions ; add more water (if necessary) until the bulk equals three ounces. Allow the fluid to stand for some hours ; then filter. Keep it a week before you use it, and then filter it a second time. I have lately stained a few slides with " Carters'" blue-black ink, diluted with water and spirits. It gives very good results, and colours specimens either a pleasant blue-black, or (if you leave the slide a couple of hours in water or spirit after staining), a gray, like the tone of a photogravure. The definition is not quite so sharp as that given by hematoxylin, but I have a retina of a spider excellently well stained by it. As I have only used it for a very short time, I should not venture to recommend it as anything very first-rate, but I think it decidedly worth trying. On the other hand, nothing can beat hematoxylin if it will only not fade. I keep my fluids— turpentine, spirits, and the stains — in three-ounce, wide-mouthed, corked bottles. These are tall enough, and the mouths wide enough to take a slide. And so, by dipping the slides first in the one bottle, then in another, as required, the trouble of mounting is greatly reduced. It is a clean process ; there is no waste ; and yet you always have ample quantities of fluids. If you have two bottle- fuls of each kind in use, you can have six or eight slides in the course of preparation at once. In conclusion, a hint or two as to the sort of insects to choose for cutting into sections will not be amiss. Those with hard chitine should be avoided, for, not only do their shells notch the razor terribly, but they also crush into the softer parts while the section is being cut, and so spoil it. Small insects are much more easily cut than large ; long and cross sections of whole insects are very instructive. Eyes are very interesting, and spiders are particularly good subjects. And, as comparatively little has been done in " sectionising " insects as yet, there is room for the enthusiastic entomologist to discover new facts, and so do a little original work. Oxford. FORMS OF CLOUD IN RELATION TO THEIR COMPONENT PARTICLES. :wE:: 7"E shall have stormy weather, sir ; those imal clouds have been about again to- day." Such was the remark made to me by a country woman in Kent, and this observation was true enough to nature : it agreed also with my own notes at the time on the appearance of "Anvil cloud,' oxfracto-cumulus. The " Ram's-head" cloud might not inappropriately be the term used to describe this drifting bank of hail or rain, which often marks the sky with such striking and fantastic outlines. Observe these dark rolling masses at sunset on an autumn afternoon, and see what kind of weather the night brings with it— driving sleet, and sudden gust of wind, with "bursts " of hail rising often to a furious and full-blown nor'wester, such as makes one thankful for a good roof overhead. The general form and type of the "Hail cloud" is pretty well known to observers of atmospheric phenomena. In most cases it greatly resembles the snow-cumulus, though generally more craggy in outline, harder in its edges, and more attended by stratus * at its base. There are, however, several types of snow-cloud. When drifting against a clear sky, the latter presents a more fleecy and softer edging, though in its general form it must be grouped, like that which originates hail-showers, with the class of "Animal" cloud, i.e. condensed t Fracto-cumuhis. Both of these are again closely akin to the Electric cumulus, or Cone-cloud (see Science-Gossip for July, 1879). This is natural enough when we recollect the frequent connection existing between the hail- shower and electrical discharges, and the part that electricity is known to play in the condensation and cohesion of the watery particles. Let us notice now that a "law" seems to hold good in regard to the origin of the different forms of cloud, and that this law is the real principle by virtue of which it is possible to forecast weather from the observation of clouds. This relation, which we may term a "law of correspondence," between the particles composing a cloud and the general form of the mass, varies its manifestations with the tem- perature and other physical conditions of the medium in which the vapoury particles are floating : yet the principle involved in the connection between the form of the body and the molecules which compose it is constant. It is a physical or chemical question to deter- mine the special forms that will be originated by given component particles under given physical con- ditions. To determine such resultant forms, in the case of previously unknown substances, is a problem * This indicates a closer affinity with the rain cloud or n"f This is the term adopted by Professor Po'ey, and indicates a mass broken by wind. HARBWICKE'S SCIENCE-GOSSIP. •difficult in the highest degree, and I suppose practi- cally insoluble in the generality of instances, except where an approximating form may be guessed at, by witnessing the evolutions that result from analogous substances. To forecast, for example, the general form which would be assumed by an aggregation of the crystals of some hitherto uncompounded chemical, would be an impossibility, except by examining the effect of known combinations almost similar in composition. Still more difficult would it be to suggest the form likely to be taken by a tree, from an examination of the seed, though even here analogy might suggest something. But it could suggest nothing as to the method of development with regard to the arrange- ment of particles, nor as to the reason of their An Owen may rebuild, from the fragments pre- sented to him, the frame of a being long extinct, whose remains lie imbedded in the bowels of the earth, and we accept his construction because we believe it to be based on the order of Nature shown by the exact observation of analogous forms. But even Owen's efforts to reconstruct would be simply abortive, and the result a falsity, were it not for the permanence and continuity of law in Nature. With- out the operation of such law within the component particles, no species either in the animal or vegetable world could possibly possess " continuity" of form. It is sufficient for our present purpose to direct attention to the relation existing between "mass" and "particle." But it is also necessary to point out that there must always be a great defect in the Fig. i. — Anvil Clouds. taking the particular form under observation. The seeds of two different plants may be exceedingly alike in general structure and composition, yet the form of their leaves and stem will present the widest possible diversity. Yet in considering the process of growth, we must not overlook the variety of elements which may be absorbed from the earth and atmosphere. It is not a question of the simple evolution of a given material into an organism from a given embryo, but of the drawing into a focus or vortex a great variety of elements, operated on by an almost equal variety of forces. The laws which regulate the operation of those forces are the laws which originate the various forms that meet our eyes, and produce a resulting structure characterised by permanence and beauty. value of illustrations from the mixing of liquids ot differing density, such as those adduced by the late Professor Jevons. The movements and elasticity of the atmosphere vary too greatly from ordinary "liquids" to allow of experiments in mixing being of much practical value in regard to known forms of cloud. And in addition to mechanical movements we have earth magnetism to deal with, which, from its known connection with auroral manifestations, may not unreasonably be thought to influence the aggregation of vapour. Samuel Barber. One of the last new things out is a watch whose face can be lit up at night by a small electric lamp. This will prove a useful watch for seafaring men. HARDWICKE'S SCIENCE-GOSSIP. CHAPTERS ON COLOUR; By S. A. Notcutt, jun., B.A., B.Sc. No. I. THE natural starting-point in this subject is the colour of ordinary bodies and pigments which we see by the aid of external light, usually white light. This light, on passing through a prism is, we know, split up into the prismatic colours, forming what is called the spectrum ; and thus we learn that sunlight is composed of rays of light of almost every different colour. On holding a piece of red glass in the path of the rays as they issue from the prism, the green and blue portions of the spectrum disappear, leaving little else than red, for the red glass absorbs the green and blue rays. Similarly, blue glass would absorb the yellow and other rays, and, in fact, with various glasses and coloured solutions, we can absorb any particular set of rays we like, and in each case the rays that remain after this process of absorption constitute the particular colour of the glass or solution. This is the case with transparent coloured bodies. In the case of an opaque body, such as a pigment, a portion of the light falling on it is reflected at the surface, and as a rule is not changed in colour ; but another portion penetrates the substance, and since the internal structure of such a substance is always irregular, this portion of the light is soon reflected back ; however, in passing and repassing through the superficial layer of the substance, it suffers absorp- tion, and hence issues forth as coloured light, the colour being what we recognise as the colour of the body. In a leaf a very thin layer of the colouring matter, chlorophyl, is sufficient to absorb all the orange, blue and violet rays contained in the incident light; hence the light reflected back from the interior of the leaf is without these rays, and since the remaining rays together constitute a green light the leaf looks green. " Thus," says Tyndall, " natural bodies have showered upon them, in the white light of the sun, the sum total of all possible colours ; and their action is limited to the sifting of that total, the appropriating from it of the colours which really belong to them, and the rejecting of those^ which do not. We may therefore say that it is the portion of light which they reject, and not that which belongs to them, that gives bodies their colours." It is sometimes convenient to be able to compare by means of a diagram the light transmitted by two different media. This is usually accomplished by taking a rectangle to represent the solar spectrum, and in it drawing a curve, the ordinates or distances measured upwards for any point of the curve repre- senting the amount of light which is transmitted of that particular part of the spectrum. On comparing the diagram of the light reflected by green pigment with that of the green light from vegetation, we find a considerable difference (Figs. 2 and 3). We see that besides a quantity of yellow and green being transmitted by the foliage green, a portion of the extreme red is also transmitted. If we therefore cut off the yellow and green light coming from foliage, we should expect it to appear red, and this is seen to be the case on viewing a garden or field through 'glass stained a deep blue with cobalt. In sunlight a piece of yellow glass should be added, to cut off the extreme blue and violet. A sunny landscape viewed through these two glasses presents a curious appearance : green trees and plants are a red colour, the sky is greenish-blue, the clouds purplish -violet, and anything orange appears blood-red. The absorption diagram of these two glasses shows that they cut off almost all the green light furnished by leaves, but transmit the bluish-green rays which leaves do not furnish. An interesting phenomenon depending on absorp- tion is that known as dichromatism, which is the variation in the apparent colour of an absorbing medium when different thicknesses are used. Thus the colour of a solution of litmus enclosed ;in a wedge-shaped glass vessel, varies from blue at the thinnest part to red at the thickest. Chromium chloride varies from green to red ; potassium perman- ganate from purple to blue ; reduced haemoglobin from green to purple. Several thicknesses of yellow glass appear red. This phenomenon depends on the principle that if a certain thickness, say one centimetre, of a medium absorbs a certain proportion of the rays, then the same proportion of the remainder of the rays will be absorbed on passing through another centimetre of the medium. In the case of litmus, suppose that in the incident light there are one hundred blue rays to every ten rays of such wave length, that they are partially transmitted by the solution, whilst rays of any other refrangibility are completely absorbed ; then after passing through an extremely thin layer, the emergent light will be a deep blue, the proportion of blue to red being ten to one, and the red being thereupon scarcely noticeable. Now suppose that each millimetre of the solution absorbs one-tenth of the red and one-half of the blue rays, then after passing through 1 mm., the light will contain nine red rays to every fifty blue, and after passing through successive millimetres of the solution, the proportion of red to blue rays will be as the table below (taken from Glazebrook's " Physical Optics "), from which it is apparent that the relative intensity of red to blue in the emergent light has altered from a proportion of 1 to 10 to one of more than 3 to 1 as the thickness, has been increased to 6 mms., and the light is finally a reddish-purple, which may be made quite red by increasing the thickness sufficiently. HARD WICKE ' S S CIE NCE- G O SSI P. Thickness. Red. Blue. mm. O IO IOO I 9 50 2 8-1 25 3 7-29 12-5 4 6-56 6-25 5 5*9 3"I2 6 5'3 I-56 In the case of most natural bodies, we have seen that the colour is due to an absorption of portions of the light in traversing a small thickness of the substance, and in the subsequent reflection from the •interior. In these cases the portion of the light •reflected from the surface itself is of the same colour as the incident light. With metals and allied bodies, this is not always the case. In the act of reflection at the surface of a metal, a partial selection takes place with regard to the rays. In the light reflected from a sovereign, yellow rays predominate, whilst the interior of a gold-plated vessel shines with a still deeper orange-yellow, owing to the selection exercised by each successive reflection. Some metals only exhibit colour on such often- a-epeated reflections. Light thus reflected from .steel becomes blue ; from silver, yellow. Another remarkable feature about metallic re- flection, is the amoujit of light reflected ; whereas white paper only reflects 40 per cent., polished silver reflects 92 per cent, of the incident light. It is these peculiarities in the nature of metallic surface which render a gilt frame so suitable for ■enclosing a painting, since it isolates it from surrounding objects, and does not intrude its own ■ colour upon the painting, since that colour is of a different character to the colour of the pigments msed in the painting. The ordinary colour of metals is then due to the components of white light, which are entirely re- flected . If we obtain a sufficiently thin sheet of a .metal, we can examine the light transmitted through it ; and this, as we should expect, will be of a different colour to the ordinary colour of the metal. In the case of gold, the light at the first surface is .robbed of its yellow rays, which are completely reflected, and the transmitted portion consists of blue or bluish-green rays. Gold can be easily precipitated i 1 the metallic state from its solutions, and being then in a very fine state of division, is capable of transmitting light. Such solutions containing pre- • cipitated gold, appear bluish-green by transmitted li^ht, and orange-red by reflected light. There are many other bodies which display similar ■colour phenomena to metals. In the case of a .crystal of permanganate of potash, the light reflected from the surface is green. The crystal itself is almost opaque, so that it is not easy to observe the colour of light transmitted through it ;, but we find that the colour of a solution of it is a deep purple, well-known as Condy's fluid. Solutions of the aniline dyes when spread on glass and allowed to dry — so as to leave a thin film of colour — display one colour when we look through them, and another when we observe the light reflected from their surface. The ordinary aniline ink (used for writing on graphs) is of a violet colour ; but light reflected obliquely from the surface of such writing is apple- green. Light reflected from the surface of a film of blue aniline is bronze. There is another phenomenon attendant on the reflection of light from metallic bodies, which is that the reflected beam is at no angle completely plane- polarised ; i.e. it always consists of two parts, one plane-polarised, and one not ; whereas, with most surfaces, at some particular angle the incident beam is completely polarised. So far we have dealt with questions of colour involving absorption. Let us now examine the results obtained by the mixture of coloured lights which is quite distinct from the mixture of pigments on the painter's palette. Various methods have been adopted for this purpose. Lambert and Heluiholtz used a verti- cal plate of glass, with a piece of coloured paper placed horizontally on each side, and observed the union of the reflected and transmitted colours. When one of the pieces of paper is yellow and the other red, their superimposed image is orange. With blue and yellow papers the image is grey. Maxwell's colour- top is one of the most convenient methods of making colour mixtures. It consists of a spindle capable of making rapid revolutions, on one end of which coloured discs of cardboard, seven or eight inches in diameter, are placed. Each disc has a radial slit to allow of other discs being combined with it, so that a composite disc can be formed with several sectors of different colours. When such a disc is rotated at from twenty-five to fifty revolutions a second, the sensation aroused in the eye by one sector has not time to disappear before the images of the other sectors are brought to bear, and con- sequently a complete fusion of the colours takes place. When a yellow and blue disc are combined and rotated, the whole appears a dull grey ; vermilion and a bluish-green also yield a grey, as do purple and emerald green. Now a surface is grey which, while it reflects white light, does not reflect so much as white paper or chalk does. Therefore we may say, that these pairs of colours produce by their mixture the sensation of white light of a low intensity. Two colours which do this are said to be complementary. Other colours when combined may produce the sensation of some intermediate colour in the spectrum. For instance, a disc half red and half yellow, when rotated looks orange. A green 8 HARDWICKE'S SCIENCE-GOSSIP. and violet disc looks blue ; a red and blue, purple. Considering the formation of the sensation of orange in this way : the colour produced is indistinguish- able by the eye from the same colour in the spectrum, but whilst the orange beam in the spectrum consists of rays of definite wave-lengths, and is not split up into further colours by passing through another spectroscope, the composite orange beam formed by the mixture of red and yellow rays, consists of rays of quite different wave-length (those corre- sponding to red and yellow), and is again split up into the original colours that formed it on traversing the large one. When the colour is a bright and intense one, the white or black must be combined with it, that is, must be subtracted from the other three. The amount of the several colours used can be determined numerically by measuring the angle- included in each coloured sector, and in this way Maxwell obtained his colour equations. Maxwell's colour-box is an apparatus by which any two or three portions of the spectrum can be made to- overlap, and the resulting light examined. This is by far the most accurate means of determining colour mixtures. ABC Re::!. Yel. Gr= Blue. Violet. Fig. 2.— Diagram of light reflected from green pigment. (O. N. Rood.1 A B C Red. Yel. Gr,1.4 Bi Fig. 3. — Diagram of light relected by green leaves. (O. N. Rood.) a spectroscope. In fact it is only the sensation of orange, which is the same as the sensation of red and yellow combined ; or, the mixture of red and yellow rays to form an orange sensation is a physiological and not a physical one. Hence we are led to conclude (in the words of Professor M. Foster), "That an orange ray awakens either a simple sensory impulse which developes into a complex sensation, or a complex impulse (formed of impulses corresponding to red and yellow) becoming converted into a mixed or complex sensation." In this respect the eye differs strikingly from the ear ; for two notes, when sounded together, do not give rise to an intermediate note. The ear is able to analyse such complex sounds more or less. The facts gathered from the above experiments with the colour-top, are included in a more general statement in regard to colour mixture which Max- well proved to be true ; namely, that by combining white or black with any other three colours, which were sufficiently dissimilar, any other colour could be matched. To assist in the comparison a smaller disc of the colour to be matched is set on the face of FLOSCULARIA ANNULATA. ALTHOUGH this flosculehas not been described, it was found (for the first time) in the summer of 1882, in a marsh pool on Tent's Muir, Fifeshire ; but only two individuals were found at that time. I sent both of them to Dr. Hudson, of Clifton. One of them died on the long journey ; the other survived, but, unfortunately, arrived in a sickly condition. It exhibited itself often enough, however, to enable Dr. Hudson to draw a very good sketch of it ; but it was in so laneuishine: a condition that it died before he could make a satisfactory diagnosis of it. In the summer of 1886, I found a few more specimens in the Black Loch, Perthshire, and this summer (1887) I have again fished a number of specimens out of the same loch ; and these have afforded me ample opportunity for studying the creature's habits. Its corona is a hemispherical cup, whose edge is cut into three lobes of unequal size, the lobe on the dorsal side being the largest. It differs from F. trilobata and F. Hoodii (whose coronne also bear three lobes), not only in the form of the lobes, but in th e HARD WICKE ' S S CIE NCE- G 0 SSI P. fact that the tips of the lobes only are crowned with short setae (Fig. 4 /) ; whereas, with F. Hoodii and F. trilobata, there are double rows of setse that run round the whole margin of their corona, a little below which are three bands or rings (Fig. 4 r) of a brown colour. The colour is due to granules floating in the fluid between the outer and inner membranes when viewed with transmitted light ; but if examined as an opaque object, with reflected light, the colour of the rings is white. (Hence the reason it has been called F. anmilata.) At the bottom of the corona, just under the third ring, is the vestibule (Fig. 4 %<), where is visible (in a good light) a contractile collar, with a horse-shoe- shaped rim, clothed with vibratile cilia (Fig. 4 cc), lips of the buccal orifice dart forward with a snap, and the prey is forced down, one by one, through the tube into the crop. The little victims may be observed wriggling about within the crop until they are caught by a pair of curved jaws which are situated at the bottom of the crop, and the entrance to the stomach (Fig. 4 /), which is called the maxillary process. The action of the jaws is an upward motion, and at the same time they open out to seize the food and drag it into the stomach. It is indeed interesting to witness the operation. Sometimes the jaws close on the spherical body of a monad a little below its centre ; and when it so happens that the jaws fail to clutch it, the spherical body rebounds back into the crop, just as a person grasping at an indiarubber ' , Fit. 4. — Floscularia anmilata, side view. Fig. 5. — Floscularia anmilata, ventral \ie\v. whose motion generates an inward current, which carries with it infusorians within the expanded mouth- funnel. When once a monad has entered into the vestibule corona, there is no escape, for if it please the palate of the floscule, its doom is sealed ; for, although the creature will suffer at times one or two monads to swim about in its large mouth, yet at any attempt to pass out over the margin, the lobes are drawn together, and the passage is closed. At the bottom of the vestibule there is a slit with two lips, called the buccal orifice (Fig. 4 bo), to which is attached a tube that hangs into a chamber called the crop (Fig. 4 c), which moves with an undulating motion. When the floscule has got one or two monads within the vestibule, the collar contracts quickly, the ball with finger and thumb a little below its centre, produces the same result. This rebound shows the toughness and elasticity of the cuticula of these minute monads. The jaws assist very little in the mastication of the food, as their function seems to be simply to drag it into the stomach. Digestion seems to be performed wholly in the stomach and alimentary canal, and these organs are lined with vigorous vibratile cilia whose operation serves to triturate the food. The ovary is an oblong sac with spherical transparent germs, but when an egg is well developed (Fig. 4,°-) it is opaque and fills a large portion of the body cavity (Fig. 4 e), and when ready for expulsion the creature retires into its tube. The egg is at first forced half out of the vent, the animal then moves slowly out of IO HARD WICKE' S S CIENCE- G OS SIP. its tube and comes to an erect position with its corona fully expanded. It then remains in that way (if not disturbed) for nearly an hour, and then again retires into its tube to finish the operation of depositing the egg- With some apparent exertion the creature lays the egg well down into its transparent gelatinous tube close to its long foot. The foot itself (Fig. 4/) is long and flexible, and is capable of great expansion and very swift contraction, for on the least alarm the creature retreats into its tube with lightning speed. A longitudinal muscle runs down the whole length of the foot and is strengthened by numerous fine muscular transverse rings from its junction with the trunk to its extremity, where there is attached a short non-contractile peduncle (Fig. 4 c) which terminates in a disk which is fastened to a leaf of sphagnum, or other aquatic plant, by a viscous fluid secreted by a gland at the extremity of the foot for the purpose. The respiratory or water vascular system in F. anmdata is not easily traced, as its trunk is rendered rather opaque by whitish granules that float in the fluid between the outer and inner membranes. But when the creature is kept for two days in clear water without proper food, the creature is so starved that it becomes very transparent, 'so that the details of the internal organs can be traced with less difficulty. The slender tortuous vessels can be observed leading down to the contracting bladder, situated near the junction of the foot with the trunk (Fig. 4 c b). The F. annulata, like. all the other species of the same genus, inhabits a transparent tube secreted by the animal itself, which not only serves to protect the creature'itself from its natural enemies, but also serves as a protection for its eggs from the ravages of aquatic worms and larvae, for although the material of the tube is tough enough to resist the attacks of a large number of worms and larvce, yet there are some, especially of the larva; of the dragon-fly, with their powerful mandibles, which cut through the tube and devour both parent and eggs. The material of the tube is so transparent that the observation of its contents is comparatively easy. The F. anmdata deposits from three to six female eggs in its tube, which take about five to six days to hatch. Six or eight hours before the embryo bursts its shell, two red eye-spots are very conspicuous ; also a ciliary motion, and a twitching of the whole contents of the egg, are observed. The twitching becomes yet more vigorous, until at last the embryo bursts through its shell and, propelled by a wreath of delicate frontal vibratile cilia, it soon finds its way out of its mother domicile, and swims rapidly round its parent ; then strikes out with a graceful motion through the water, poking amongst the weeds in quest of a fitting place to start housekeeping on its own account. It seems to be rather particular in selecting a site to build its future residence. I have seen one alight on the leaves and axil of a plant in a dozen places, before it made a final selection of a spot to fix its foot ; and a few hours after the young floscule was encased in a thin gelatinous tube, with its foot, trunk, and corona (although smaller in size) developed in the same form as its parent. I have not yet met with the male of F. annulata, nor even the male of the other three-lobed species. There are sixteen known species of the genus Flos- cularia ; the males in eight of them only have yet been found, leaving the males of eight species to be discovered. The males of those that have not yet been found are F. rcgalis, F. Mira, F. longicaudata, F. Algicola, F. trdobata, F. Hoodii, F. annulata, F. edentata. The males of those species that have been discovered are F. coronctta, F. ornata, F. cornuta, F. cydops, F. catnpamdata, F. ambigua, F. calva, F. mutabdis. The whole sixteen species of the genus Floscularia are inhabitants of fresh water, with the single ex- ception of F. ornata, which is now known to inhabit both fresh and salt water. I had the good fortune to find the F. ornata very plentiful in tide pools at the mouth of the Firth of Tay in the summers of 1885 and 1886. The length of full-grown specimens of F. anmdata is from B?T to 35 of an inch. John Hood, F.R.M.S. Dundee. FURTHER NOTES ON THE TOOTHWORT {LATHRsEA SQUAMARIA). EACH year, since 1883, when I first found L. squamaria in the locality indicated by G. E. Smith, in his " Plants of South Kent," published in 1829, I have visited the place, and on each occasion have found the plants all bearing the characters I described in Science-Gossip, January, 1884. In connection with my notes of that date, I would remark that it has been thought that Smith's plant was an old one, gone to seed, and that mine was a young, imperfectly developed plant. The editor's note, page 143, vol. xx. was in reference to specimens I .sent him in full seed, and which were quite as crowded as the plant photographed by me. I have not yet found any plant in the least approaching that described and figured by Smith. The plants I gathered in 1S83 were growing in a section of the copse, which I will call for reference No. 1, and which had remained undisturbed for, I should say, from fifteen to eighteen years. There was but little undergrowth; the hazels, &c, being well up. In an adjoining section of the same copse (No. 2) of about two years' growth, I, together with several others, searched most assiduously for the plant, but without success. During the winter of that year, No. 1 section was cut down, and in 18S4 there were HARD WICKE'S SCIENCE- G OS SIP. IT comparatively few specimens to be found, and none in No. 2 section. In 1SS5, I found but three specimens in No. 1 section, and again none in No. 2. In 1886, I could not find a single plant in No. I section, although I paid several visits, and took with me several good searchers ; but in No. 2 section I found two plants. In 1S87 I was still unable to find any plants in No. r, while in No. 2, which is now about six years old, I found the plant in comparative abundance. Of course, during the first few years following the cutting down of a copse, the undergrowth is very considerable, and the difficulties of finding so small a plant as L. squamaria are great. But I feel convinced, from my experience, that its appearance is influenced (like that of some other woodland plants) by the condition of the copse with regard to its undergrowth. That it has a most remarkable vitality, the following (communicated to me by G. B. Wollaston, Esq., of Chislehurst) will show. He informs me that he had a plant of Z. squamaria in a flower-pot for about twenty years, during which time it never appeared above ground, but that at the end of the twenty years it was as sound and fresh as when first put into the pot. Its not appearing above ground was of course due to its want of food supply, it being parasitic. Plants that have acquired the habit of parasitism — whether partial or complete — may naturally be expected to afford evidences of the time when they lived free and independent lives, in the retention or partial retention of organs or peculiarities of structure, which were absolutely necessary for them in their free and independent condition, but which are now of no further service to them, the host performing the function for the plant which its own structure enabled it then to perform for itself. • The animal world affords numberless instances of useless and aborted organs, evidently remnants of a ■previous condition of existence requiring a different organization ; and in the vegetable world, no doubt, the instances will be found as numerous when the same amount of attention has been given to it. We already know of many modified leaves, aborted and imperfectly developed styles, &c. &c., and as cur knowledge of the physiology of plant-life increases, it may reasonably be assumed that many remnants of a past condition will be discovered. That they will be so marked and diverse as in the animal world we should not expect ; the functions and surroundings of the one being so many and various in comparison with those of the other. Z. squamaria affords us several remarkable and interesting features, illustrating "adaptation to environment " and the modification of organs to perform functions other than those primarily per- formed. The peculiar fleshy scales of the plant under con- sideration I believe to be an excellent illustration of the retention of organs no longer of service to the plant for their original function, and of the modifica- tion of those organs, adapting them to the performance of a new and totally different one. If a transverse section be made of one of these scales, it will be found to possess several irregularly-shaped cavities (Fig. 6), and on the walls of these cavities will be found numerous little gland-like bodies. These little bodies have been noticed by many observers ; but what special function they perform has not (so far as I can learn) been hitherto discovered. In addition to these gland-like bodies, and scattered between them on the surface of the cavities will be seen numerous symmetrically arranged cells, reminding one of stomata. What function, however, could stomata possibly perform in this enclosed cavity ? Certainly not the ordinary function of respiration. But that they are stomata, although perhaps useless and aborted, I think I have sufficient evidence to prove. Also that the little gland-like bodies are really glandular hairs, which, together with the stomata, occupied their usual position on the inferior side of the leaf of the plant before it acquired its parasitic habit. How, why, and when Z. squamaria took upon itself the habit of parasitism, are questions that can be answered by speculation only. That the habit was acquired gradually, we infer from observation — since changes in habit, and still more in structure, can take place but slowly. Probably the first act towards parasitism was the developing of cells, which, coming into contact with some other growing vegetable substance, had the power of attaching themselves to it ; and as Z. squamaria is a succulent, rapidly-growing plant, it helped itself to the nutriment of its neighbour through these attached cells. This habit gradually grew until the plant became, as we now find it, wholly dependent for its existence on some strong and vigorous host. Probably this proclivity to parasitism was brought about by the circumstances of its environment. What these were we cannot know ; but that the habit became necessary to its existence we may be sure, and also that the cells possessing the function of attachment and absorption must be considered as a development or adaptation for this special function. As the habit of parasitism developed, the leaves and roots would gradually give up their own special functions, and, if suitably positioned, would adapt themselves to the new order of things ; the plant either losing them entirely or partially, or modifying them to new functions. Thus the leaves of Z. squa- maria appear to have become modified. An examination of the very young scales will reveal the fact, that they have apparently started life as ordinary leaves ; instead, however, of develop- ing a flat blade, as in an ordinary leaf, the young leaf takes a sharp bend downwards, and folds back upon itself, as in Fig. 7. The cells of the leaf 12 HARD WICKE ' S S CIE NCE- G 0 SSI P. which come into contact, clue to this folding back, are apparently possessed of the power of uniting, and thus forming the cavities seen in a longitudinal section. The formation of these cavities is due to the linear growth of the aborted leaf; the bending back of the leaf first takes place, as just remarked, when very young and small. Points, probably of the raised ribs near the apex, are brought into contact with other points near the base ; attachment takes place, thus forming the first cavity ; the leaf, by growth, increases in length, both between the points of attachment and the apex, and the same points and the base, which, afier proceeding a certain distance, again come into contact and unite, forming a second cavity, and so on (Fig. 7). A transverse section reveals cavities that radiate from the stem. These are probably caused by the uniting of the underneath ribs of the leaf; for through each partition wall, between the cavities, may be traced the vascular bundles which ran through the ribs of the leaf in its earlier history, and which are continued through the base of the leaf into the stem, as seen in the transverse and longitudinal sections (Figs. 6 and 9). The cavities in the scale are sometimes separate and distinct from each other, but more generally several, or even all, are united, forming one large cavity with deep recesses. The apex of the leaf or scale, folded back upon the base, is never attached cell to cell, the tissue here never being continuous. It is, however, in- variably pressed quite close ; so close indeed, that in the cavity of a fully-developed scale I have never found any extraneous matter (I shall, however, refer to a younger scale later on). Fig. 9 is a fair example of the numerous scales I have examined. Hence, though these cavities are not hermetically sealed by cell-fusion, they may be considered practically air- tight, and may thus be correctly termed enclosed cavities, and, as such, they will render the stomata useless. It must not, however, be forgotten that the united cavities converge to the apex, which suggests that some time in the past they were in communication through an opening here, with the outer air ; and also the probability of the stomata carrying on their function in a gradually lessening degree, until the opening was finally closed. With regard to the method of development of the scales, I am at a loss to determine whether it is due to a folding back, and attachment taking place as described, or whether, after the folding back, caused by the cells of the ribs not being developed at the same speed as those of the lamina, has taken place, these former are (subsequently) developed with a speed equal to the growth of the lamina cells, and continuity is thus preserved. This appears to me to be a question presenting great difficulties, ss it is highly probable that both methods obtain ; the first in order being the method by attachment, gradually superseded by the continuous method, which latter may be replaced in course of time, if needed, by the production of the thick fleshy scale, without any break in the continuity of its tissue from the stem. From these observations it will be seen that, which- ever way the development of the scales may take place, it is such that the stomata and glandular hairs of a previous condition are enclosed in cavities, which may, in the course of development, altogether dis- appear, cell tissue taking their place. If it be true, that the leaves of L. squamaria have become aborted as leaves, and developed into Fig. 6. — Transverse section of a fully-developed scale, showing arrangement of cavities and vascular tissue. X 4. Fig. 7. — Longitudinal section of scale, illustrating the method of the folding back of the lamina, and the formation thereby of the longitudinal cavities. X 12. thick fleshy scales, it then follows that these scales must have a definite function to perform, for it does not appear feasible that such large and numerous appendages should be retained and developed without serving some purpose in the economy of the plant. The primary function of these scales I believe to be one of food-storage ; the attachments of the plant to its host, as we shall presently see, while perhaps numerous, and in some cases very complete, do not seem sufficient to maintain the rapid growth of the thick succulent stem, the comparatively large flowers, and the production of the numerous seeds. The HARDWICKKS SCIENCE-GOSSIP. 13 period of the year in which L. squamaria blossoms (viz. April) is, of course, one in which great activity of growth is going on in the host, and food supply .-hould be abundant. But, however complete the attachment may be to the host, there must be some limit to the speed at which food materials can be supplied, especially when it is considered that at this host's activity, during which, when not appearing above ground, it was storing up material in its scales for its next flowering. In August, 1886, I dug up a plant (previously marked) on which the scales were about half-grown, and with the flower-spikes about half an inch long. (Shown exact size in Fig. 10.) This points to conditions such as obtain in the Fig. 8. — Stomata and glandular hairs in cavity or scale, (a) stomata ; (i) a stoma, with guard cells removed ; [c) glandular hairs ; [d) stem cells of glandular hairs. X 220. _,_ t-Li . , Fig. 11.— Cavity of young scale with spores and mycelium of a fungus enclosed. X 50. Fig. 9.— Longitudinal section of fully-developed scales, show- ing the connection of the small cavities with one another, also the unattached apex. X 4. Fig. 10. — Flower spike, as found in August, 18S6. Fig. 12. — Transverse section of underground stem near the base, showing attachments to the host (hazel), [a) Hazel root : (b) vascular tissue of host ; (c) vascular tissue of parasite ; [d) parenchyma of parasite ; (e) parenchyma of host; (/)two small rootlets of the hosts attached ; (.r) sections of young scales. X 7. time the host is needing all its resources on its own account. It certainly would be strange if, during the seven months' activity of the host, a period of only five or 'six weeks was utilised by the parasite. The most natural act (if I may so describe such an un- natural proceeding) would appear to be, that the parasite took advantage of the whole time of the Orobanches, which remain under ground for several years, occupying the time in storing up food-material in the large scaly bulbous base of the stem ; so in all probability does L. squamaria store up in these fleshy scales the necessary supplies for the period of flowering. The cellular tissue of fully developed scales is 14 HARDWICKE'S SCIENCE-GOSSIP. crowded with starch granules ; and, after flowering, many of the scales may be found in a half-decomposed state, quite black and exhausted. In addition to this function of food-storage, I am inclined to think (but of this I have at present but little evidence), that the epidermal cells of the scales have the power of attaching themselves to any suitable root with which they may come into contact. But although I have searched very diligently, and washed very carefully, I have not yet succeeded in securing any example showing such attachment. In the first place, the attachment, if any, is but very slight, and in the next, the soil in which I find the plant is very clayey and difficult to remove ; but, from several specimens I possess, exhibiting an altered or abnormal condition of some few of the epidermal cells, I am strongly of opinion that they possess this power. This leads me to the consideration of the mode in which L. squamaria attaches itself to its host. Dr. Trimen, in his very interesting article on " Parasitism of Flowering Plants," in the " Popular Science Review," July, 1873, mentions, "... thick tooth-hkc scales, from the axils of some of which slender rootlets are given off. The observations of Mr. Bowman, in 1829, first showed that upon these rootlets were borne the absorbent tubercules. Carefully washing away the soil will show these attached to the rootlets of the supporting plant, and a section through both displays a perforating cone penetrating the bark at least, and, as I am informed by Mr. Stratton, actually pushing its way into the very wood." "Without questioning the accuracy of these obser- vations, I must confess that I have been unable, so far, to discover any such rootlets. I have found many rootlets of the host and of other plants — growing near — interwoven, as it were, between the scales and stem ; and when it is considered that the soil in which the plant grows is invariably dense with these rootlets, it is not surprising that they should be found so interwoven. The only attachment that I have been able to discover and fix with certainty, is that which the parasite makes to its host, at and near the extremity of its underground stem. Here it seizes upon, and absorbs into itself, the rootlets of its host, the union usually being so complete that it cannot be deter- mined where the one begins or the other leaves off. Not only the parenchyma, but the vascular tissues also unite, so that the one is continuous with the other. Near the end of the stem the number of host-rootlets absorbed is sometimes very great, a thin transverse section frequently showing four or five attachments ; the rootlets seized are sometimes very large. It is beyond these attached rootlets that the branching of the underground stem takes place. I have found as many as fourteen branches upon one such stem ; and on none of these have I been able to discover any other attachment, with the exception of the doubtful one mentioned in connection with the scales. If, then, this is the only attachment, weight is added to my conclusion that the function of the scales is that of food-storage. In a previous paragraph I have mentioned the fact of not having found any extraneous matter in the cavities of fully-developed scales. In several young ones (gathered in 1885 and 1886), I have, however, found the mycelium of a fungus in great abundance, and have been fortunate in getting sections showing the spores of this fungus developing. As these spores are a considerable size (too large to get in after the closing of the cavity), I am of opinion that they are enclosed by the folding back of the leaf. Fig. 11 represents a cavity with spores and mycelium en- closed. I am not acquainted with L. clandestina, the other European species, or with any other foreign ones ; but it would be interesting to know whether they resemble L. squamaria in the several charac- teristics mentioned, or whether the modification of the scales, if any, is at a different stage. With regard to the allied genus Orobanche — O. picris, O. caryophyllaceiT, O. major, and O. minor — the only species of which I have any knowledge — the method of attachment is very similar, the tissues of host and parasite so coalescing that it is very difficult to trace the connection. In Cuscuta the haustoria are distinct cells, pene- trating the tissues of the host. So in Pedicularis, Rhinanthus, and Melampyrum ; but in these the attachment is very slight indeed, and quite different from that which obtains in the Orobanchaceae. W. T. Haydon. Dover. RUDIMENTS AND VESTIGES. IN an article which appeared in the October issue of Science-Gossip, I remarked that, " In the sense in which the term Rudimentary is repeatedly to be found in ' The Descent of Man ' (i.e. to express the supposed 'vestiges of structures existing in early types'), it is a contradiction to the theory of evolution." Your correspondent, Mr. F. G. Fenn, defends Mr. Darwin's use of it, and confidently asserts that there is a "double meaning" for " the word." He gives two explanations, the exact opposite of one another ; the first expressing, " vestiges of structures existing in early types" — i.e. something left behind from a once fully developed organ, at the very end of its existence ; and the second expressing " the fore- shadowings or beginnings of structures in process of devolopment." How these two contrary meanings can be given to the same word requires explanation. That Mr. Darwin employed the term in the former HARD WICKE ' S S CIE NCE - G O SSI P. i5 sense is evident, as " vestige " and " rudiment " are used by him interchangeably, and his own explanation of the word " rudimentary" is as follows. He says, " In order to understand the existence of rudimentary organs, we have only to suppose that a former pro- genitor possessed the parts in question in a perfect state, and that under changed habits of life they became greatly reduced." But he especially contra- dicts the latter meaning attributed to him by Mr. Fenn. Far from stating that rudimentary organs are "beginnings of structures in process of development," Mr. Darwin explains that they "are either absolutely useless," or "tending in this direction," and that they must be distinguished from "nascent organs," which, he says, " on the other hand, though not fully developed, &c, are capable of further development." From this it is plain that in the one sense only does Mr. Darwin allow that the word is used by him ; and to show the confusion of ideas that the retention of the terms in this sense is bound to involve, was the object of my paper. Mr. Fenn's statement that " many able anatomists and naturalists would now use ' vestiges ' in the place of 'rudimentary,' " only tends to suggest a doubt of its correct application. Why should vestigial be substituted, unless rudimentary appeared unsuitable ? And we have only to refer to its derivation, and to the authority of numerous writers, to perceive at once that it is eminently unsuitable. Dryden, Addison, Bacon — all used the word rudimentary in its true sense of "first, inaccurate, unshapen, beginning or original of anything." With Shakspeare, Locke, Milton, and others, it also meant "first principles and first elements" ; and many authors of repute might be quoted to confirm this as the rightful use of the word. Only, I believe, among modern scientists would the strange perversion of the word be found. Mr. Fenn is of opinion that I have read Mr. Darwin's works with a "preconceived idea" of their teaching ; but I am bound to acknowledge that if I had any bias at all, it was strongly in favour of the honest, painstaking scientist ; and if Mr. Darwin, by his persistent accuracy, has taught his readers to submit terms as well as facts to a strict investigation, he would have been the last to complain of the jealous regard for truth which cannot sanction the misuse of a single word, even were that word misapplied by himself. To Mr. Fenn's question, "Why should we claim perfection for ourselves, and deny it to all other organisms ? " I reply, that, arguing upon evolution grounds, we are bound to look upon anything lower than the ideal form as an arrested development ; and, for the sake of the argument, I adopted that position. The subject being a very wide one, and requiring more room than may be claimed for mere corre- spondence, I should be glad at any future time to answer the query in full in an article, could space be afforded me to do so. I cannot quite reconcile Mr. Fenn's question with the two following statements in his paper. He says, " Perfect as all our organs are at the present, we have no reason for supposing that evolution has reached a limit," &c. Are all our organs perfect at the present time ? Then why does your correspondent object that " Miss Layard would take man as per- fection " ? It seems that we are agreed in this particular. But the next sentence is perplexing. Mr. Fenn continues, "Of all our organs which we have handed down to us, &c, som have been developed, &c. ; others, falling into disuse, have become partially degenerate." Here are two state- ments hard to reconcile. "All our organs," we are told, are "perfect at the present time," but some of our organs "have become partially degenerate " ! As it is impossible here to enter at any length into the vast subject of evolution, I would return to the special point at issue — namely, the advisability of retaining or re- jecting the word "rudimentary" in the sense in which it is used by Mr. Darwin. Unless abetter excuse can be made for its retention, it would still appear to be misleading and incorrect. Nina F. Layard. ASTRONOMY AND METEOROLOGY. By John Browning, F.R.A.S. THE observations made at the Royal Observatory of the Collegio Romano during April, May, and June, give particulars of the distributions of the solar spots, faculre, and protuberances, and a table of the numbers and comparative extent of the spots and faculce observed from July to September. A great diminution took place in both spots and faculse towards the end of August, and in the intervals between the 23rd of August and the 2nd of Sep- tember, and the 51I1 to the 12th of September, no spots or faculae were seen. At the meeting of the Royal Astronomical Society, held on the nth of November, a letter from Mr. Roberts was read, in which he offered to place at the disposal of Fellows of the Society photographic negatives of stellar groups which will enable them, by using a proper microscope and micrometer, to obtain, by measurement, results that may be useful to astronomy. Professor Pritchard read a paper on Further Researches in Stellar Parallax by Photographic Methods. Mr. Creswick exhibited some photographs of star- groups which had been taken at Greenwich with the Sheepshanks Equatorial on curved plates, to determine the extent of the field that would be made use of for purposes of measurement. The result i6 HARDWICKE'S SCIENCE-GOSSIP. obtained was that for purposes of accurate measure- ment, a field of 4 deg. might be used, and a field °f 5 deg. where only approximately accurate results are required. On January 28th, there will be visible a total eclipse of the moon, beginning at 9.30 p.m. Meteorology— Ax the Royal Observatory, Green- wich, the highest reading of the barometer for the week ending 19th November, was 30-22 in. on Wednesday morning, and the lowest 29-11 in. on Saturday morning. The mean temperature of the air was 34-1 deg., and 7-6 deg. below the average. The general direction of the wind was east and north-east. Rain fell on two days of the week, to the aggregate amount of 0-53 of an inch. The duration of registered bright sunshine in the week was 11 -o hours, against 13-7 hours at Glynde-place, Lewes. For the week ending 26th November, the lowest reading of the barometer was 29-17 in. at the beginning of the week, and the highest 29-84 in. on Wednesday evening. The mean temperature of the air was 38-7 deg., and 2-3 deg. below the average. The general direction of the wind was north-east. Rain fell on four days of the week, to the aggregate amount of 0-31 of an inch. The duration of registered bright sunshine in the week was o-2 of an hour, against 2*7 hours at Glynde-place, Lewes. For the week ending 3rd December, the lowest reading of the barometer was 29-47 in. on Tuesday morning, and the highest 30-31 in. on Friday morning. The mean temperature of the air was 43 '3 deg., and 1-9 deg. above the average. The general direction of the wind was south-west. Rain fell on three days of the week, to the aggregate amount of 0-48 of an inch. The duration of registered sunshine was 7-4 hours, against 11 • 1 hours at Glynde-place, Lewes. For the week ending 10th December, the highest reading of the barometer was 29*86 in. at the beginning of the week, and the lowest 29-13 in. on Thursday evening. The mean temperature of the air was 40*4 deg. and 2-2 deg. below the average. The general direction of the wind was westerly. Rain fell on four days of the week, to the aggregate amount of 0*47 of an inch. The duration of registered bright sunshine in the week was 2-9 hours, against 9-1 hours at Glynde Place, Lewes. January is the coldest month in the year. The mean temperature at the Land's End is 45 deg., while in the plain of York it is only 38 deg., the difference being due to the influence of the Atlantic. Travelling from south-east to north-west, the mean temperature of some of the principal towns is approximately as follows :— Truro, 44 deg. ; Ply- mouth, 43 deg. ; Exeter, 42 deg. ; Dorchester, 41 deg. ; Portsmouth, 40 deg. ; and London, 39 deg. The average rainfall in January is 5 inches from the Land's End nearly to Exeter ; 4 inches in Devon and Dorset ; 3 inches along the South Coast and through the greater part of the south of England, from Bristol to Canterbury ; 2 inches through Cheshire and the Midlands to the Essex coast ; and only 1 inch along the East coast from Newcastle to Ipswich. GOSSIP ON CURRENT TOPICS. By W. Mattieu Williams, F.R.A.S., F.C.S. BUYS-BALLOT— On the 16th of November last, the University of Utrecht worthily instituted a festival in honour of the fortieth anniversary of the "doyen des meteorologistes," M. Buys-Ballot, at the same time founding a prize of a gold medal to be given every ten years for memorable work in meteor- ology, the first, of course, being then given to the venerable professor. This is not the place for a sketch of Buys-Ballot's life-work, and if it were, it should be drawn by some one knowing more of the subject than I do. But there is one simple and important generalisation to which his name is attached that should be better known than it is among us here. I allude to "Buys- Ballot's law " concerning the winds and barometric gradient. This gradient has more to do with weather prediction than the height of the barometer at any particular place. If the barometer be either high or low or medium at such place, and of nearly the same height at other places all around, immediate change may be expected ; but if that place be in a steep barometric gradient, i.e. if the barometer is much higher or lower at other places beyond it, a change is imminent. If the barometer at a given time stands one-tenth of an inch higher at Edinburgh than at London (both corrected to sea-level), there is a moderate gradient ; with a difference of half an inch there is a steep gradient, indicating unsettled and stormy weather. These gradients may be easily traced on the weather charts published by some of the newspapers. The curved lines, usually dotted, are isobars, or lines of equal pressure, against which are marked the height of barometer all along that line ; the direction of the wind is marked by arrows. Buys-Ballot's law, in the northern hemisphere, is that, if you stand with your right hand towards the region of higher barometer, and your left hand towards lower barometer, the wind will blow against your back ; or vice versa, if you stand with your back to the wind, the barometer gradient is ascending on your right and descending on your left, or the opposite if you face the wind. You may test this law by taking such imaginary positions on one of the weather charts, and observing the relations of the arrows and isobars to yourself. HARDWICKE'S SCIENCE-GOSSIP. n The African-Mediterranean project.— Among the grand projects of M. de Lesseps'was one for cutting a canal from the Mediterranean on the coast of the Gulf of Gabes, in order to flood that neighbouring part of the desert, a large area of which is supposed to be below the sea-level. There appears to be a hitch somewhere ; either the depression proves, on further survey, to be much less than was originally supposed, or there are difficulties in the cutting, which was at first described as very easy. The project, however, is not to be abandoned. Com- mandant Landas, who is there apparently as the agent or representative of M. de Lesseps, has ascer- tained the existence of underground waters in the region in question, and is at work sinking wells, one of which yields 1S00 gallons per minute, another 2000 gallons per minute. These wells are sunk for the purpose of fertilising the district, and thus afford- ing support to the labourers who are to work upon the canal which is to supply the projected inland sea. Carbonic acid in School-rooms. — Experi- ments have been recently made by W. Fossek on the quantity of carbonic acid in an unven- tilated school-room before and after the meeting of the class. In three determinations made before the pupils entered, he found the air to contain respectively 0*078, o,OQ2, and o-oS8 per cent, by volume. After three hours' occupation by the class of fifty-eight scholars, it contained o-620, 0*637, and °'557 Per cent., or between seven and eight times as much. Besides this there are the bodily exhalations, which are still worse than the carbonic acid. The practical lesson taught by these facts is, that wherever school accommodation is at all limited, the pupils should clear out for a run between each lesson. Basic Cinder as Manure. — Further study of the manurial efficiency of the cinder obtained by applying the Thomas-Gilchrist, or basic process, in Bessemer steel-making from very bad pig-iron, ^brings out higher estimates of its value. Many such in- vestigations have been made on the Continent during some years past, and quite recently Aitken has published his results in the " Transactions of the Highland and Agricultural Society " for 1887, p. 245. He compared basic cinder containing 40 per cent, of phosphate of lime with Curacoa phos- phate containing 87 per cent., Canadian phosphate, 59 per cent., and Carolina phosphate, 57 per cent. ; and found that when applied to the soil under cor- responding conditions, it was about as effective as the above-named phosphates. He attributes this superiority, in proportion to its constituent phos- phorus, to its finely-ground condition as supplied in the market ; but Dr. J. M. H. Munro ascribes it to the great relative solubility of the phosphate of lime contained in it. There is but little difference between these explanations, so far as practical application is concerned. The important fact is that the basic process brings forth a vast quantity of buried phos- phates that may be laid upon the surface to increase the food supplies of the world, and that it does this at a smaller expense than such phosphates are other- wise obtainable. Manure from Granite. — Intimately connected with the above in its economic bearings is the use of felspar as a manure. It contains potash, one of the absolutely indispensable constituents of fertile soil, and that particular one which is the most liable to be wastefully washed away, owing to the free solubility of the nitrates, chlorides, sulphates, and carbonates of this alkali. But the silicate that exists in the felspar is the one excep- tional salt of potash that is not freely soluble. It is slowly decomposed in the presence of water and carbonic acid, and is thus gradually supplied to the plant-roots as they require it. If, however, the fel- spar were added to the soil in lumps like the natural crystals, the process of solution would, on the other hand, be too slow ; but by grinding it to a certain degree of fineness the just medium is attainable. Mr. Aitken describes, in the " Transactions of the Highland Agricultural Society," some experiments made at Pumphuston on turnips, and at Boon on peas, with felspar ground sufficiently fine to pass through a sieve of 120 meshes to the linear inch. On the turnips the felspar did better than an equivalent quantity of sulphate of potash, on the peas not so well. Seeing that we have mountains of granite and porphyry largely composed of felspar, and these in sterile regions, the fact that we can produce valuable manure by simply crushing the boulders and other rock fragments that cumber the ground, and adding to the powder some phosphates of lime, such as the waste cinder of ironworks above described, opens a wide field for agricultural enterprise. We hear much about the emigration of the London "unemployed." They need not be transported across the Atlantic, nor to the Antipodes ; there is work enough for them in the reclamation of Dartmoor and the granitic wastes of Cornwall, and they would do the work well and cheerfully under arrangements that would ultimately render them the owners of the land they had rendered fertile. The Rabbit Plague in Australasia. — The magnitude of this scourge is not yet sufficiently appreciated in our hemisphere. It it remains un- checked, it practically amounts to the ruin of the otherwise most hopeful region of the world. But there is now some hope. Pasteur has come to the rescue, and science is to be applied. Most of my readers will have learned how, ere this will be published. Chicken-cholera broth is to be sprinkled on tempting herbage, the rabbits are to eat this, and, i8 HARDWICKE'S SCIENCE-GOSSIP. '"having done so, they are to propagate an infection that will wholly or partially exterminate them. "A consummation most devoutly to be wished for ! " So far the project is most promising, but the danger to the poultry and game of the country is rather serious. Pasteur answers for the sheep. He has tried, and finds that they are not liable to this particular infection. Among the birds of New Zealand is one vile luxurious beast whose extirpation is most earnestly demanded. It is that epicurean parrot, that feathered gourmet, which has discovered in the kidney suet of the living sheep a food more dainty than the vegetable oil of its natural seed-food. The hateful bird accordingly fixes its claws in the wool of its victim, and tears away its i-kin with cruel beak ; then dives amidst the warm blood and quivering flesh into the fat surrounding the kidneys, while the tortured sheep struggles in vain to shake off its tormentor, and dies after suffering the most dreadful agonies that are possible to such an animal. If Pasteur's remedy fails, there is anolh :r direction open for research. May we not find some herb that will poison rabbits ? If so, it could easily be planted in small patches, carefully enclosed with wooden stakes at about six inches apart, too close for sheep or lambs to pass, but free to rabbits. In dry weather they will eagerly devour almost anything that is succulent, and these little plantations might be watered, if necessary, during Australian droughts. Wolves in France. — It is a curious fact that, ■while Pasteur is coming forward to rescue the Austrabans from their four-footed pest, the ancient and classical quadruped scourge of France is in- creasing so seriously that, only five years ago, the French Government found it necessary to raise the head-money on wolves. They now offer 200 francs for killing a wolf that has attacked human beings, 350 francs for one in young, 100 francs for a male wolf, and 40 francs for a cub. In 18S2, 423 wolves were killed; in 1883, 1316; in 1884, 1035 ; in 1885, 900; and in 1886, 760. When living in Flintshire, I paid a rate of two- pence per acre as mole-catchers' tax, the result being ■that at certain times a mysterious personage groped mysteriously in the fields ; and on the following •morning two or three black objects were seen hanging to wires. These were moles, and the wires were parts of traps which were supposed to have caught the moles. Libellous persons asserted that the same moles were exhibited again and again in different fields, and that the mole-catcher was a mole-preserver, as extermination of the moles would ruin his trade. With such high awards for the killing of French wolves, the like may occur in France, if wolf-catching is a profession. A pair of wolves and family might be carefully fed until the cubs reached the 100 francs or 200 francs stage of life, and the enterprise would probably yield a good profit to the peasant on whose land they were reared, and who, knowing their habits, would gather his wolf harvest at the proper season. SCIENCE-GOSSIP. A capital new illustrated monthly has been brought out in the United States, under the editorship of Dr. Manton and others, entitled " The Micro- scope." The London agent for it is Mr. W. P. Collins, 157 Great Portland Street, W. We have received a copy of Mr. J. G. Goodchild's elaborate paper on " Ice-work in Edenside, and some of the adjoining parts of North-Western England," reprinted from the Transactions of the Cumberland and Westmoreland Association. In last month's number of " The Welcome " is a lengthy, well-written, and elaborately-illustrated article, by Mr. II. M. J. Underhill on " The Beautiful Floscule." The account of the Microscopical and Natural History Soiree of the Croydon Club, on Nov. 19th, reached us too late for notice in our last. It appears to have been highly successful, in spite of a foggy night. The list of objects of science was enormous. The Ipswich Scientific Society held their three years' Conversazione in the Public Hall, on Nov. 29th ; about 800 people were present. The hall was lit by electricity conveyed by wires over the house-tops from the office of the "East Anglian Daily Times," more than a quarter of a mile away, and the same electric energy was also utilised to work the machinery. A new book by Dr. J. E. Taylor, editor of Science-Gossip, is announced under the title of " The Playtime Naturalist." It is to be copiously illustrated. The Swiss "Journal of Ornithology " announces the extinction of the last Alpine Vulture or Lammer- geyer. The last specimen believed to be remaining is now in the Museum at Lausanne. Mr. Norman Lockver's articles on Meteorites, now weekly appearing in "Nature," have attracted much attention, asbeing original contributions to the theories of Cosmogony. A KEEN controversy has been going on in the same journal between the Duke of Argyll and Professor Bonney, relative to Darwin's theory of the " Origin of Coral Reefs." The district Calabria was again visited by a terrible earthquake on December 1st. The National Association for the Promotion of Technical Education, recently held a most successful meeting in Manchester, at which Sir Henry Roscoe, HA RD WICKE ' S S CIENCE- G 0 SSI P. *9 Professor Huxley and others made powerful speeches. The association is about to extend its sphere of agitation to Liverpool, Glasgow, Newcastle, and other large towns. Mr. Goschen's Presidential Address to the Statis- tical Society on December 6th, obtained much public attention. His statistical inferences are most valu- able at the present time. The Howietoun Fishery records the successful exportation of salmon ova to New Zealand, viz. : One hundred and thirty-five thousand in the S.S. Kaikoura, three hundred and sixteen thousand in the S.S. Doric, and one hundred and twenty-five thousand in the S.S. Tongariro, making five hundred and seventy-six thousand salmon ova, which were obtained from the Forth, Tay, and Tweed Districts. The whole of the consignments arrived in good condition. The American land-locked salmon {S. sebago) and the rainbow trout (S. irideus) have done well during the past season, but did not spawn last spring. It is hoped, however, they will do so next. The cross between S. levenensis and S. salar $ proved fertile last winter and has been re-crossed with levenensis — thus : S. levenensis has been crossed by (S. levenensis X S. salar g) <j, and produced the largest fry at present in the Fishery ; and (S. levenensis X S. salar parr <$ ) has been crossed by S. levenensis <$ , the produce being fair fry. Thus it now appears probable that trout may be improved in size by the in- troduction of salmon blood without sacrificing fertility. A "Flora of Hertfordshire " is announced. It is by the late A. R. Pryor, and will be edited for the Hertfordshire Nat. Hist. [Society, by Mr. B. D. Jackson, Secretary of the Linnean Society, with an Introduction on the geology, climate, botanical history, &c, of the county, by Mr. John Hopkinson, F.G.S., and the editor. MICROSCOPY. Nobert's BANDS. — Ihavea slide of Nobert's bands, and I find it is ruled to fifteen bands. Can any reader tell me the distance between the lines of the fifteen band slides ? — Micro. Knock's Slides. — We have received sketch 17 of Mr. Enoch's famous Entomological Studies. It is the only authentic drawing of the notable Hessian Fly, from exact measurement. Accompanying it is sketch 18 of the "Fairy Fly " {Camptoptera papaveris), an exquisite object under the microscope. Another Evening at the Royal Micro- scopical Society.— The " Scientific Evening" of the Royal Microscopical Society, held on the 23rd November, in the Library of King's College, was a great success. The most important exhibit was the display, by Dr. Crookshank, of a series of micropho- tographs of many kinds of Bacteria. These were- shown in the Doctor's Laboratory, by means of the Oxyhydrogen lantern. Dr. Crookshank was very successful in his demonstration, which had a two-fold object. Firstly, to show how capable photography is, to depict these delicate organisms ; and the value such results possess, in the facility for demonstrating their portraits to numerous students in a class, with absolute fidelity ; and, secondly, to show, that, although many persons believe the various Bacterio- logical forms to be all alike, more or less ; yet, the fact is, when sufficiently high magnification is em- ployed, as in the case of these photographs : it is clearly seen that each bacteriological form is quite specifically distinct ; and no two forms seem to be quite alike. The various species seem to possess almost as much individuality of character as the various seeds of plants, when placed under the microscope. The lecture, and the examination of the objects and apparatus, in the Doctor's laboratory, proved most instructive and interesting. In the library a great number of most interesting displays were made. Mr. Michael, the much-loved President of the Quekett Club, exhibited a rare species of Phalangium. The cyclosis in vallisneria was well shown by Mr. Ingpen, under an Apochromatic quarter- inch objective. Messrs. Beck had a good display. Powell and Lealand's exhibit, as usual, was superb. In one microscope they were giving results upon Ampliipleura pellueida, with the analyser of the Polariscope placed over the eye-piece. There was a collection of Polyzoa shown by Mr. Hardy : Mr. Hailes was showing objects, chiefly Foraminifera, under a Stephenson's binocular. Mr. Dadswell was showing the cyclosis in a bulblet of Chara (a mar- vellous sight, one I had never before seen) : also, some splendid specimens of " Pond Life," notably a very large Amceba prineeps, of unusual activity. Mr. E. T. Browne made quite a sensation with an abundant collection of his new find, Orthesia insignis^ of all sizes and ages, alive in a cork cell under a four- inch object-glass. These insects were the admiration of everybody. To most persons present, they were the. greatest novelty in the room. Then there was an< exhibition by another gentleman of a living house-fly, regaling itself with sugar. Mr. Rousselet had a fine Floscularia ornata. Messrs. Watson had some re- markably beautiful slides of insects' eggs, diatoms, &c. Mr. Freeman showed a collection of consecutive sections of insects, prepared by Mr. Underhill, whose skill in this direction is wonderful. Mr. Fitch had a lot of clever dissections of spiders. Mr. Nelson was showing Ampliipleura pellueida in the manner in which he only can. Mr. Enock exhibited the Hessian Fly, and a lot of his clever sketches of many minute Hymenopterous insects. Baker's table, as usual, had a fine display. The new apochromatic lenses, and what they can be made to show, were well illustrated. The well-known podura scale was splendidly shown. 20 HARDWICKE'S SCIENCE-GOSSIP. There was also some new apparatus by Zeiss. Mr. Badcock exhibited " Pond Life," some rare finds. Our old friend, the larva of Tiresias scrra— memorable for the settlement, many years ago, of the question, " Whence is obtained the object, figured in all the microscopical works as ' Hair of Dermestes ' " (vide Science-Gossip, October 1865, and the early dis- cussions reported in the journal of the Quekett Club), — put in an appearance, to remind one of old errors cleared away ; lor the object, so well known, is not got from Dermestes at all. Mr. Groves displayed -the structure of a glandular hair of Drosera, an insect-eating plant ; and Mr. Grove illustrated the recent botanical discoveries as regards the continuity of protoplasm in the medullary rays of certain plants. The beautiful microscopic drawings made by the late Mr. Draper were on view. The readers of Science- ■Gossip have seen a few of these, associated with the chapters on " Graphic Microscopy," which appeared two or three years ago ; and from these specimens, will be able to judge of the quality of the whole collection, which will probably become the property of the Royal Microscopical Society. The genial Mr. Charters White was in good form, with his capital album of microphotographs. That man is always " to the front; " and so is Professor Stewart, who showed a very pretty object from a Crustacean, never seen before. He told me it had no scientific interest, though I and others found it to be very, very curious. There were several interesting mineralogical slides, and many other exhibits worthy of special notice. Many old friends turned up ; and there were many joyful recognitions of old microscopists whom we have not seen for years. On a former occasion (Science-Gossip, 1875, page 16), I thought it worth while to record a most interesting Scientific Evening on 9th December, 1874; and this latter display is equal to it. It shows that the old society is as vigorous as ever, although so many of its then energetic Fellows have "joined the majority." — S. J. Mc I nt ire. ZOOLOGY. IIyalina glabra, var. eicolor. — This variety is mentioned in the "Journal of Conchology," 1886, p. 86, but has never been described. It differs from the type in having a whitish or pale umbilical region, which is more or less sharply defined from the brown colour of the rest of the shell. The interest of this form, which was taken at Bromley, Kent, lies in its being apparently a case of atavism. According to the theory that the brown colour represents the dark bands of other Helicidae suffused over the shell, this variety bicolor is a case in which the suffusion has not taken place lower than the edge of the fourth band, leaving the original ground-colour in the umbilical region. It may be well to state that the H. glabra is Zonites glabcr of Jeffreys, and the H. alliaria of some Continental authors, though not of Kobelt.— T. D. A. Cockerel I, West Cliff, Custer Co., Colorado. H. arbustorum, M. sinistrorsum.— In the last number of the "Journal of Conchology" (Q. J. C, s. 225), Mr. J. W. Taylor records the only two sinistral specimens of Helix arbustorum, L., which he knows. A third specimen was recorded in the May-June number of the " Nachrichtsblatt d. d. Mai. Ges.," for this year (p. 76), by Herr Tschapeck. He found it in Styria, near Mittendorf, in the meadows of the Salza. The specimen was perfect and mature, with a curiously-depressed spire, colour- ing not mentioned. The specimen figured in Ferussac belonged to M. Charpentier, and was found near Gryon, in Canton Vaud. — Brockton Tomlin, B.A. Scarcity of V. atalanta in 1887. — I wonder if Lepidopterists in general have noticed a scarcity of V. atalanta during the past season ? Though I have been in the country all the summer and autumn, and have been constantly in the open air, generally for five or six hours every day, I have only met with a single individual of this species. I can hardly think that this was owing to any want of observation on my part, especially as I could only find two caterpillars, though I must have searched several hundred nettle- beds for them. Last year I got fourteen caterpillars without making any careful search for them, and in due course I saw several dozens of the perfect insect. — R. B. P., Eastbourne. The Zoological Society of Glasgow. — The third meeting of this society for the session was held on Monday, 14th November, the Rev. E. Walters, president, in the chair. One new member was elected. Mr. J. MacNaught Campbell showed a black racer (Coluber alleghaniensis, Hoi.), and a blue racer snake (C. constrictor), from North America, both exceeding five feet in length. The same gentle- man exhibited several garter snakes (Tropidonotus saurita, Linn.), and a small rattlesnake (Crotalo- pJiorus tergemimis, Hoi.), which, although only a few inches in length, was quite capable of defending itself. Mr. G. G. McKenzie exhibited several diving spiders (Argyroneta aquatica) with their nests from his aquaria. The secretary showed skins of an old female and young male " Old English " black rat (Mus raltus, Linn.), caught recently in Glasgow. This species — which is now almost extinct in Britain — is hardly ever found now in this district, having given way before its larger and more powerful relative, the common brown rat. — IV. Hannau Watson. Colours of Cocoon Silk. — At a recent meeting of the Entomological Society, Mr. E. B. Poulton exhibited the cocoons of three species of Lepidoptera, HARDWICKE'S SCIENCE-GOSSIP. 21 in which the colour of the silk had been controlled by the use of appropriate colours in the larval environment at the time of spinning up. lie said this colour-susceptibilty had been previously proved by him in 18S6, in the case of Satitniia carpini, and the experiments on the subject has been described in the Proc. Royal Society, 18S7. It appeared from these experiments that the cocoons were dark brown when the larva; had been placed in a black bag ; white when they had been freely exposed to light, with white surfaces in the immediate neighbourhood. Mr. Poulton stated that other species subjected to experiments during the past season, afforded con- firmatory results. Thus the larvre of Eriogaster lacustris had been exposed to white surroundings by the Rev. W. J. H. Newman, and cream-coloured cocoons were produced in all cases, whilst two or three hundred larvae from the same company shun the ordinary dark brown cocoons among the leaves of the food-plant. In the latter case, the green surroundings appeared to act as a stimulus to the production of a colour which corresponded with that which the leaves would subsequently assume. Mr. Stainton suggested that larvae should be placed in green boxes, with the view of ascertaining whether the cocoons would be green. It had been suggested that the cocoons formed amongst leaves became brown because the larvae knew what colour the leaves would ultimately become. BOTANY. Tree-growing after Girdling. —In May, 1879, I attempted to kill by girdling a tremulous poplar- tree, which, by its position and the numerous suckers it threw up from its wide-extending roots, interfered with my orchard. I cut off a strip of bark twelve inches wide entirely around the tree, at a spot about a foot from the surface of the earth. The part left bare seasoned over that year, but the tree did not die ; however, it shed its leaves earlier than others of the same species. It grew on the next year, as if nothing were the matter till the autumn, when the foliage assumed unusually brilliant colours of red and yellow a full month before there was any change on the other trees. It continued growing during the third year subsequent to the girdling, but with diminished energy, and the leaves changed their hue at the close of summer, and fell very early in autumn ; and next spring, 1881, the tree was quite dead. I should mention that it did not put out its leaves just so early in the spring after being girdled, as it would otherwise have done. I have read in the " Scientific American " of a somewhat similar experiment, with the difference, however, that the Vermont tree kept growing on above the ring, and increased in three years five inches in circumference above, while it remained of the same girth below. There was no such exceptional phenomenon in the tree with which I dealt in co. Armagh.—//. W. Lett, M.A. Flowers and Fruits.— At pp. 11 and 12 of Dr. . Taylor's most interesting and suggestive " Sagacity and Morality of Hants," I find, " A leaf is a much more highly-organised vegetable production than a petal. . . . Flowers are frequently terminal . . . borne . . . where the uprising sap . . . must be poorest and thinnest." This, of course, I quite understand. On pp. 14 and 15 there are descriptions of flowers of the gentians, etc., being produced "at great physiological expense " to the plant ; added to this, of course, it is well known that plants expend a great deal of energy on the all-important process of ripening their seeds." I should be glad if any one will explain how fruits obtain the amount of nourishment they require for this purpose, placed as they are in the same position on the plant as the flowers, which are, to a great extent, because of their position "aborted and degraded" and starved leaves. — A. G. Tansley. Yew-Trees, their Size and" Age. — I have been, with my friends, measuring several big yew-trees in the south-east corner of Hampshire. Will you allow me to state the result in Science-Gossip, with a- view to learning about other big yews, and with a view to description as to their age ? I give the cir- cumference— the smallest circumference of each of four trees in three neighbouring churchyards. ft. in. 1. In Warblington Churchyard . 18 4 2. ,, Redhampton ,, . 20 o 3. „ do. ,, . 20 5 4. ,, S. Hayling „ . 33 o Reckoning a year for every line of diameter, or twelve years for every inch, this would give to the Hayling tree, with a diameter, say, of 11 feet, or 132 inches, an age of 1584 years. Will any of your readers contribute any information as to big yews ; their size, and the mode of ascertaining the age ? — P. J., Emsivorth. Campanula glomerata. — I was very much sur- prised to find a number of plants of this species in full flower in the first week of the present month of November. They were on the Downs, near Beachy Head. I suppose this unseasonable blossoming is to be attributed to the plants having been kept back by the extraordinary drought of the past summer. I found, too, on the loth of November, plants of Gentiana campestris in flower ; these, too, I suppose,, had been delayed by the drought. Those botanists who have only seen C. glomerata in localities where it attains its normal development, would scarcely recognise it as it is found here, where it does not exceed an inch or an inch and a half in height, and where it usually has only one flower, which looks like a little blue star, as it peeps out of the short grass. — R. B. P., Eastbourne. 22 HA RD WICKE'S SCIENCE- G 0SS1P. Fungus Crop of 1887.— I can fully corroborate your correspondent, Mr. Waddell, in his note of last month, as to the remarkable scarcity of fungi during the past season. As he has remarked, this is more particularly noticeable with regard to the pasture species, always excepting the common mush- room {Agariats campestris), which seemed to be peculiarly abundant. In fields where last year I could have gathered basketfuls of the various species of Hygrophorus, scarcely a single specimen was to be found this year, and many of the species I have •entirely failed to notice. In localities where for years I have never missed a supply of Lepiota rachodes and L. procerus, not a single specimen appeared this year. Woodland species do not seem to have been so scarce, although they too have been erratic. I never remember seeing such a general profusion of Faxillus involutes, and Boletus edutis was also wonderfully prolific ; one small patch never failed to supply me with a luscious dish three times a week for a couple of months. The Lactarii also seemed to be more than usually abundant, but the Russulse appeared to be scarcer than common. Species which grow upon either dead or living trees were ■comparatively plentiful ; and I was fortunate in find- ing several rich supplies of Tricholoma pcrsonata, which I have hitherto found to be scarce in this district. — J. P. Soulier, Bishop Auckland. "The Annals of Botany."— No. 2 of this serial is published, containing papers by Sir J. D. Hooker, on " Hydrothrix, a New Genus of Ponte- deracere," by F. W. Oliver, " On the Obliteration of the Sieve-tubes in Laminaria ; " ' "The Life- history of Lycopods," by F. O. Bower; "On the Terms Phyllome and Caulome," by F. O. Bower ; "On the Absorption of Water, and its Relation to the Cell-wall in Mosses," by J. R. Vaizey ; "On the History of Certain Plants, as Alexipharmics, or Snake-bite Antidotes," by D. Morris ; " Notes on the Genus Taphrina," by B. L. Robinson; and a host of various Botanical Notes, by S. H. Vines, Schon- land, Bower, Isaac Bayley Balfour, etc. ; altogether making up a magnificent series of contributions to practical botany. GEOLOGY, &c. Encroachments of the Sea. — For some time past, the sea has been encroaching on the pretty little town of Cromer (Norfolk), which is situated on the top of an extensive range of cliffs, and, during the sea's encroachment, it has exposed a forest bed. During the last month or two the sea has been " hard at work," and has shown extensive beds of clay, pebbles, cakes of lignite, blue clay, and numerous fragments of wood, including two large trees, supposed to_be fir. The following Mammalian remains, with many others, have been found : — Tarsal bones of Elephas, distal joints of Bos, calcareum of Cervus libra, joints of cervus, portions of -lower incisor of Trogontherium, astragalus of Cervus, portion of hyaena's jaw, with teeth missing ; several fish vertebrae, a few bones of Platax Woodivardi ; also several root- stocks of Ostnunda rcgalis which have not been pre- viously found near Cromer. This interesting section is now filling up with sand, and in a little time will no doubt disappear. — J. B. B. NOTES AND QUERIES. Yellow (or Ray's) Wagtail. — For two or three days during the past week, my garden was visited by this pretty little bird, which I had never before observed here. I counted ten at one time on quite a small lawn, which had been newly mown, and they had evidently pounced upon some dainty insect, as they were not at all discomposed by a cat which eagerly watched, and tried to spring on them, but when disturbed, soon flew back again. The sun shining at the time displayed the brilliant yellow ot the breasts of some to great advantage. Is it not unusual for them to come so near a town ? — S. J\I. P., Weymouth. Munchausen Science. — (Science-Gossip, page 226). — Paragraphs under the heading of Popular Science are worse than useless when facts are not strictly adhered to, and any one who tries to prevent erroneous statements being perpetuated does good service to science. The statement that 20 or 30 feet is no uncommon length for a specimen of the marine worm Nemertes Borlasci appears to Mr. Williams an exaggerated magnification, and he refers to the subject under the above title. Is, however, the statement wrong, in fact, and should it be ascribed to the Baron ? I express no opinion whether Kingsley's " Glaucus," published in 1859, may or not be re- garded as containing "pretty stories founded on fact ; " but, as to the size of the worm, I would refer your readers to Dr. Mcintosh's monograph of the British Nemerteans, published by the Ray Society in 1874. He says (p. 183) in his description of it, " Body 15 to 30 feet, to as many yards in length, and from I to 4 lines in breadth. . . . even now I am not quite satisfied about the limit of its growth, for after a severe storm in the spring of 1864, a specimen was thrown on shore at St. Andrews which half filled a dissecting jar 8 inches wide and 5 inches deep — 30 yards were measured without rupture, and yet the mass was not half uncoiled." — H. Bamsden, M.A., F.E.S. Lacuna pallidula. — Can' any correspondents tell me why, though Lacuna pallidula and Lacuna vincta are described as " plentiful on our shores," we so seldom find even an empty shell, especially of L. pa/lidulat Which kind of sea-weed is it the animal feeds on ? I have not yet succeeded in getting a living specimen of any Lacuna. — C. E. Gubbins. Lapidary Work. — In answer to F. Hay ward rarrott's enquiry on " Lapidary work " I beg to send the following extract from "English Mechanic," August 5th, in answer to any enquiry on " Polishing Pebbles." "Here are a few hints which may be useful, and if the querist should happen to be at the seaside next autumn, he may see the work done. HA RD W1CKE S SCIENCE- G OSSIP. The apparatus which the lapidaries, who abound at every seaside town, use for cutting and polishing pebbles, is usually of the roughest kind. The tools required are : a lathe of the most simple description, a piece of sheet- iron or tin-plate about four inches in diameter, rounded and fitted to the lathe like a circular saw, a tool like a butcher's steel, with a square point tempered hard, a slab of Bath stone (flag), and a small piece of Water-of-Ayr stone (known in lithography as snake-stone, or the latest name given it is Tam-o'-Shanter stone). The circular plate dips into a trough containing a mixture of emery, quartz, sand, and water. With it the pebbles may readily be sawn into slices. The slices must then be affixed to a wooden face-plate by means of a cement composed of resin, shellac, and Venice- turpentine. You will thus be enabled to turn them to the desired shape. They are polished by rubbing on a flag of Bath stone with a little fine emery. This will make them pretty smooth. To get a fine polish rub them in the same manner, using putty powder instead of emery, or you may rub with Water-of-Ayr stone. To give the operator a command of the stone he is polishing, it is usual to fix it in the centre of a flat piece of wood, about two feet long, with the cement before mentioned. The stone must be kept wet whilst being operated upon. Many of the pebbles found on the sea-shore contain fossil remains, which are brought out in a striking manner by polishing, and as the substance in which the fossils are imbedded is frequently semi-transparent, the pebbles may be dried and used as photographic negatives." — 6". Mason, Gloucester. Poisonous Fungi.— Could any of your botanical readers supply me with the names of the fungi eaten in the two fatal cases of poisoning which occurred in Northumberland, and at Bexley, Kent, in September ; also in any other fatal case ? — JP. F. G. Types of Storm Clouds. — I do not know whether Mr. Barber is really serious in proposing the fantastic names for clouds which he gives, but it really seems that if we go into the classification of clouds after his fashion, we shall have a list as long as a "main t' gallant bowline." What is wanted is a simple classification for ordinary observers, and a complex scientific one for those more advanced ; a classification of clouds into two families of Strati- forius and Cumuliforius meets the former case, and an extension of this, as proposed by the Rev. Clement Ley, the latter. A knowledge of forecasting can never be gained if simply the forms of clouds are to be noted : a meteorologist must understand the con- ditions on which the clouds are formed first, then de- duce his forecast from this. — David Wilson Barker, R.N.R. Badges worn in Time of War. — I have had in my possession for a great number of years, for it was given to me by the daughter of an English officer who served in the American War of Independence — ■ a seed-ball of the American "button-tree," which I was told had been worn in the button-hole of an officer of the American party at the Battle of Bunker's Hill, as a " distinguishing badge." My specimen presents the appearance of having been so worn — the fruit-stalk has been twisted until it has been reduced to a bundle of fibres, which together are so strong and tough that there would be much difficulty in breaking them. Is there any record of these curious "button-balls" having been so worn by the soldiers who took the American side in the War of Independence ? — Francis Brent, F.S.A., Plymouth. Fish Culture in France. — M. Jousset de- Bellesme, Director of the Trocadcro Aquarium, who- for the past two years has been endeavouring to acclimatise American salmon in France, has just given a lecture on the subject, explaining the results achieved so far. In June last year, he deposited, 22,000 salmon fry of the American species hatched in the Aquarium at eleven points of the basin of the Seine from Rouen to Les Andelys, in batches of 2000. The fish were then a trifle over four inches in length. In October following a few of the fish caught in the Loing and the Iton were found to have increased to nine inches. Owing to the great mortality among the small fry hatched this year, which M. de Bellesme attributes to the substitution of Seine water for the- pure water from the Vanne, he has succeeded in. rearing only 10,000 salmon fry and 40,000 trout. Munchausen Science. — When sending you a paragraph a few days ago, in reference to this heading, I had not noticed that Mr. Bolton had already (p. 237) called the attention of your readers- to MTntosh's British Annelids. — H. Ramsden. NOTICES TO CORRESPONDENTS. To Correspondents and Exchangers. — As we now publish Science-Gossip earlier than formerly, we cannot un- dertake to insert in the following number any communications which reach us later than the 8th of the previous month. To Anonymous Querists. — We must adhere to our rule of not noticing queries which do not bear the writers' names. To Dealers and Others. — We are always glad to treat dealers in natural history objects on the same fair and general ground as amateurs, in so far as the "exchanges" offered are fair exchanges. But it is evident that, when their offers are simply disguised advertisements, for the purpose of evading the cost of advertising, an advantage is taken of our gratuitous insertion of " exchanges " which cannot be tolerated. We request that all exchanges may be signed with name (or initials) and full address at the end. R. C. C— Get Stark's "British Mosses," coloured plates, price -]s. 6d. W. Hannan Watson. — Apply to Mr. Henry Laver, F.L.I. , Trinity Street, Colchester, for information concerning the black rat, etc. H. W. Lett. — Your paper on the " Sunflower" shall appear shortly. Colonel. — Saliicus tardigrarfus'is not an uncommon species of spider. You will find a full account of it in Staveley's '^British Spiders," and also in Dr. Blackwall's work on British spiders. G. W. Bulmer. — We shall be pleased to receive any paper you may send us. A. Bennett (Croydon). — Unfortunately your paper arrived too late lor the January number, as we had to go to press very early on account of the holida) s. G. E. East. — There formerly existed a " British Natural History Society," but it was in reality for the purpose of dis- tributing sets of specimens to subscribers. We believe it has. ceased to exist. EXCHANGES. For exchange, back vols, of" Entomologist," "Young Natu- ralist," "Union Jack," "Naturalist," also odd numbers of " Entomologists' Monthly Magazine," and other periodicals ; full list sent on application. Dragonflies wanted in exchange. — W. Harcourt Bath, Ladywood, Birmingham. Skins of weasel, hedgehog, and long-eared bat, etc.; speci- mens of Sirex gigas, Gonepleryx rhamni, Lyaena argwlus, and scores of other Lepidoptera. Wanted, dragonflies in good condition.— W. Harcourt Bath, Ladywood, Uirmingham. Collection of British land and freshwater shells, all mounted and named, also minerals, fossils, marine shells, etc., offered for dragonflies, either British or foreign.— W. Harcourt Bath, Ladywood, Birmingham. Wanted, foreign frogs and toads, alive, preserved in spirits, or otherwise.— W. Hannan Watson,; 219 St. Vincent Street,. Glasgow, N.B. 24 HARDWICKE'S SCIENCE-GOSSIP. Offeked, Indian pappoose-holder, doll, redstone fipe bowl, tow and arrows, buckskin tobacco-pouch, mocassins, land, freshwater, and marine shells. Wanted, land, freshwater, and marine shells, especially from southern countries. Send lists. — Thomas E. Addy, 54 North Franklin Street, Janesville, Rock Co., Wisconsin, U.S.A. Wanted, British ferns and grasses in exchange for flowering plants or books. — J. W. B., 56 Vine Street, Liverpool. An herbarium of British plants and mosses for what offers? — J. H. Lewis, F.L.S., 145 Windsor Street, Liverpool. A collection of botanical books and others for other books of general interest. — J. H. Lewis, F.L.S., 145 Windsor Street, Liverpool. Wanted, a genuine clutch, with full data, of eggs of golden eagle, must be Scotch. — G. T. Phillips, Wokingham, Berks. Wanted, Pisidium roseum, Bytkiiiia Leachii, Limnaa glu- tinosa and involuta, Testacella haliotidca, Helix laincllata, ffelix pyg)ii<ra, Helix obvoluta, Bulimus moktanus, Clansilia biplicata, and Acme lineata. Good exchange. — F. R. Fitz- gerald, Clifford House, Harrogate. Wanted, vol. i. of Dr. Jeffreys' "British Conchology " and Hartings' " Rambles in Search of Shells." — F. Fitzgerald, Har- rogate. Wanted, fossil land and freshwater shells. Good exchange. — Fit7gerald, Harrogate. Wanted, eggs of barn and long-eared owls, jay, chough, Dartford warbler, green woodpecker, red grouse ; also nests of British and foreign birds. Good exchange. — Fitzgerald, Harro- gate. For exchange: — Coins. — Silver: Elizabeth. Copper: Jas. II., Wm. III. & Mary, Wm. III. Copper: Guernsey (8 doubles and 4 doubles), St. Helena (halfpenny), Nova Scotia (halfpenny), Columbia, Sierra Leone Company li anna). Silver: Hong Kong (10 cents). Copper : Belgium (5 cents and 2 cents), Nor- way : Carolus XIV. (2 shillings), Carolus XV. {2 ores), Oscar (5 skilling). Canton Schwyz (2 rappen). Eggs. — Wild duck, moorhen, plover, red-backed shrike, great tit. — F. R. Arundel, Friends' School, Saffron Walden. Nevada diatom deposit, clean, i oz., for four good diatom or foraminifera slides, or for equal quantity of other cleaned diatom deposit. — Hutton, Mottram, Manchester. Microscope, in good condition, monocular body, A and C eye-pieces, three objectives forming one, frog plate, animalctila cage, condenser, &c. ; will exchange for J-objective or offers. Wanted, stage micrometer ; will exchange live or dead speci- mens of Hydropkilus piceus (beetle). — W. Turner, 89 Terminus Road, Eastbourne. Wanted, Science-Gossip for Feb. 1884, having a coloured plate, in exchange for that of Jan. 1884, with coloured plate, or -one mounted parasite micro slide. — T. S.Morten, 28 Haverstock Hill, L .ndon, N.W. Wanted, eighteenth or nineteenth century tokens or coins, or medals ; exchange, fossils from chalk, Thar.et sands, etc. — Fred. Stanley, Margate. Has any reader a superannuated rain gauge to dispose of? Required for class illustration, not for actual rain measurement : its being defective for latter purpose will not matter, if perfect enough to illustrate the principle. — Wm. Jacobs, 12 Selwyn Villas, Munster Road, Fulham, S.W. Any reader of Science-Gossip possessing a catalogue to one of the £$ $s- collections of minerals and fossils by the late Mr. T. Tennant (149 Strand), is requested to communicate with — H. J. Torpey, 120 Gower Street, W.C. For exchange, scales of roach and black snake of Australia for microscopical purposes. Minerals: sylvanite (telluride of gold), auriferous quartz, Labradonte. Shells : Tapes virgiuea, Cyprtea pantherina, Pentunculus glycimeris. All kinds of natural history objects wanted in exchange ; also books on natural history. — E. O. Meyers, Richmond House, Hounslow, W. Wanted, to exchange a number of good dried specimens of North American plants for continental or other foreign species. Will also exchange with N. American collectors, giving British and Continental in exchange. — A. E. Lomax, 56 Vauxhall Road, Liverpool. I .itmenes coarctata, some splendid cells containing live grub of this rare insect, all British. What offers ? — F. Dolamore, Avenue Road, Bournemouth. Wanted, live or dead specimens of Vitrina pellucida and varieties ; exchange given in freshwater shells. — W. E. Collinge, Springfield Place, Leeds. Liassic and magnesian limestone fossils offered in exchange for mountain limestone fossils. — John Hawell, M.A., In^leby Vicarage, Northallerton. Micro Slides.— Pollen of Salvia patens, in glycerine jelly ; Sphcerocrystals of cactus, dry; i liragmidium bulbosum, in C. B. ; and Phragmidittm gracile, in C. B. ; to exchange for other mounts. Mutual approval.— Rev. H. W. Lett, M.A., Aghaderg Glebe, Loughbrick'and, co. Down. Mosses. — Wanted, to exchange mosses from north of Ireland with former or new correspondents. I have Climacium den- droides in fruit. — Rev. H. W. Lett, M.A., Aghaderg Glebe, Loughbrickland, co. Down. For exchange, Dilatatus and others for other land and water shells. — Sam. Cluugh, 21 Abingdon Street, Blackpool. Wanted, British marine shells in exchange for Vaccaria " 'ggh'i, Dudrcsnaia coccinea, and other rare algae. — Mrs. Hodgson, Chalgrave Vicarage, Leighton Buzzard, Beds. First-class lantern slides, 3i X 3i, consisting of photo-mi- crographs of insects (whole and part), insects and vegetable parasites, diatoms, botanical subjects, etc. ; list sent. Wanted, good micro slides, microtome, J-inch or i-inch objective, or offers.— W. D. Stewart, 2 Gilmore Terrace, Edinburgh. For exchange, " History of British India," by Edward Thornton,_ 184s, 6 vols., cloth 8vo, in good condition; "The Law relating to India and the East India Company," 1841, cloth 4to., published at £3 3s. Books on natural history taken in exchange. — E. O. Meyers, Richmond House, Hounslow, W. A few good slides of spread diatoms in Tolu in exchange for other slides of Diatomaceae — spread preferred. Send list. — E. B. L. Brayley, Rockdeane, Hughenden Road, Clifton, Bristol. Ammonites, British and foreign, wanted ; exchange in fos- sils, etc.— John Hawell, M. A., Ingleby Vicarage, Northallerton. Large collection of foreign shells offered in exchange for British. — Miss Linter, Arragon Close, Twickenham. Good collections of minerals, including many fine and rare cabinet specimens; also collections of Echinodern s. Will ex- change for good shelis ; list on application. — Miss Linter, Arragon Close, Twickenham. Unio margaritifer {{xom the only known Lancashire locality) and A. cygnca and vars. for specimens of same species, or U. tumidus and U.pictorum from other localities. — R. Standen, Swinton, near Manchester. Wanted, tropical marine mollusca. Offered, "Popular Conchology," by Agnes Catlow, 1843, describing families and genera, with 312 woodcuts ; also " Common Objects of the Sea Shore,'' by Rev. J. G. Wood ; "Geology for the Million," by M. Plues ; and "Insect Transformations," part 2, 1810. — W. J. Jones, jun., 27 Mayton Street, Holloway, London, N. Well-mounted slides of Foraminifera, Echinodermata, Po- lyzoa, Diatomacese, fish scales, crystals, and spicula, in ex- change for other well-mounted slides ; lists exchanged. — W. M. Ranson, The Cottage, Priory Road, Anfield, Liverpool. British and foreign specimens of marine and land shells offered for others not in collection. — J. T. T. Reed, Ryhope, Sunderland. Harting's " Rambles in Search of Land and Freshwater Shells," coloured plates, and "Reign of Law" (Argyll), for continental Anodons or Unios, or good figures or tracings of same. — George Roberts, Lofthouse, Wakefield. Engravings of varieties of Anodons and Unios for specimens of shells of various forms of British or continental anodons or Unios. — George Roberts, Lofthouse, Wakefield. BOOKS, ETC., RECEIVED. "Bees and Bee-keeping," vol. ii., by Frank R. Cheshire (London : Upcott Gill). — " Living Lights," by Charles F. Holder (London : Sampson Low & Co.). — " The Creator and Creation," by W. H. Dallinger (London: T. Woolmer). — "The Micro- scope," translated from the German of Professor Carl Naegeli and Professor S. Schwendener (London: Swan Sonnenschein, Lowrey, & Co.). — " Elements of Mineralogy," by F. Rutley (London: Thomas Murby).— "The Young Collector Series: Ants, Bees, Dragonflies, Earwigs, Crickets, and Flies," by W. H. Bath (London: Swan Sonnenschein, Lowrey, & Co.). — "The Photographer's Indispensable Handbook," by Henry Sturrhey (London: Iliffe & SonK — "An Elementary Treatise on Light!and Heat," by Rev. F. Wilkins Aveling, M.A., B.Sc. (London: Relfe Bros.). — " Elementary Microscopical Manipu- lation," by T. Charters White (London : Roper & Drowley). — "Proceedings Folkestone Nat. Hist. Soc." — "Geology of Portland Promontory, W. Victoria," by G. S. Griffiths. — "Ottawa Naturalist" — "Journal of Conchology." — "The Microscope." — "The Naturalist's Monthly." — "Annals of Botany," No. 2. — "Journal Quekett Micro. Club," Dec. — " Feuille des Jeunes NatiTalistes." — "Essex Naturalist" — "American Monthly Microscopic Journal." — "Journal of Microscopy" — "Century." — "Gentleman's Mag." — " Bel- gravia." — "Midland Naturalist." — "Wesley Naturalist." — "American Naturalist." — "Victoria Naturalist." — " Garner." — " Amateur Photographer." — " British Dogs," No. 13.—" The Naturalist." — &C, &c, &c. Communications received up to the 8th ult. from : J. S.— F. M.— C. P.— H. D. G.— C. P.— Rev. H. W. L.— A. G. T.— F. R. A.— H.— F. R. F— J.— W. B.— C. W. D.— J. E.— P. J— T. D. A. C— R. G. W.— L. N.— G. A. P. C— J. J. M. I. -A. G. T.— J. H. L.— J. E.— W. H. W.-F. S.— X. H.— W. J.— R. P.— F. C. G.— H. J. T.— E. C. M.— A. H. A.— J. B.— W. T.— E. A. H.— A. R.-T. S. M.— A. E. L.— W. A. C— H. H.— E. O. M.— B. T.— Dr. S.— G. R. —P. F. G.—J. T. T. R.-W. M. R.— G. E. E., jun.— T. W.— W. J. J., jun.— T. W. C. -R. S.— L.— J. H.— W. E. C— E. B. L. B.-E. C. M.— E. C— T. S.— W. D. S— T. C— E. S. — C. P. L.— J. B. B.— S. C— F. E.— J. E. F.-Rev. J. E. W. —J. C.-C— A. T— H. P. S.— J. E.-B. T.— C. L. L.— R. D. P.-T. H. -A. R I. W.-&C HA RD WICKE' S S CIENCE- G OS SIP. 25 NOTES ON GEOGRAPHICAL DISTRIBUTION. By T. D. A. COCKERELL. S year by year Science becomes more complicated, and the array of ascertained facts so vast as to be far beyond the grasp of any single brain, specialism must of necessity exist, and not only this, but to know anything thoroughly one must be more cr less a specialist. Nor is this to be regretted, since nearly all the knowledge of later days has been gained from work- ers in particular groups, and it is certainly true, that the man who knows one group well knows the principles of life, heredity, variation and distribution, so far as they can be known, and is able to apply these principles with nearly equal facility to other groups. Yet there is one kind of specialism very rife that I do protest against, as being productive of inconceivable misconception and narrowness of mind ; that specialism which studies a group only as it occurs in a particular country or district, and cares nothing for its distribution or variation without that limit. And in thus protesting, I do not wish to say anything against local lists, which to me have the greatest value, or against those who give most attention to the fauna of their own district, for it is most natural and right that each should study what comes most directly under his observation, but against the feeling of contempt for all foreign species, and that ignorance which knows that Vanessa antiopa is a very rare butterfly which used formerly to be found at Camber- well, and thinks there is nothing more to know. No. 278.— February 1888. My object, therefore, in this paper, is to rouse up some measure of interest in the foreign distribution of our British species among those who have hitherto regarded them from the British standpoint alone, and to show how we owe much of our native fauna to immigration, and on the other hand have from time to time sent forth emigrants to people other lands. In a former note I attempted to divide up the British Mollusca into three sections, the Northern, Eastern, and Western ; or otherwise, the Boreal, Germanic, and Lusitanic, and asked for adverse criticisms upon this arrangement, so that it might be put to the test. Dr. Kobelt, in an article published in Germany, took exception to the classification of a few species, but agreed with it in the main, and beyond this nobody seems to have disputed my division of our fauna, which is based upon that proposed by Forbes many years ago. The circumpolar region it maybe supposed, was at one time temperate in climate, and possessed a fairly uniform fauna and flora. Cold coming on, drove all forms of life southward, and hence the same species appeared simultaneously in Central Europe and Central North America, meeting and mingling with the" fauna of the south — and thus was formed our British boreal fauna and flora. Next, the question arises, how are the boreal types to be distinguished from the eastern and western ? Their distribution in Britain is certainly some guide to this ; the northern forms being mainly prevalent in Scotland and the North and West of Ireland, in which last district they mingle with the western ; but Planorbis parvus — certainly a boreal type, is found in Devonshire and Surrey, and Cochlicopa lubrica is universal. One test alone seems to me a sure one, and that is by comparison with the North American fauna : — Whatever form in Britain is represented in North America by an identical or very nearly allied species belongs to the boreal type, except such as have been introduced by human agency, and perhaps certain migratory species. Possibly, it does not always exclude a species from c 26 HAREU'ICKE'S SCIENCE-GOSSIP. the boreal fauna that it has no representative in North America, since there are forms peculiar to Northern Europe and Asia which are not American ; yet I myself should be disposed to regard these as belonging rather to the Germanic than boreal type — as for instance, Li max cinereo-niger, which I had formerly considered boreal. Another difficulty, and this a more serious one than might be supposed, is that of distinguishing which are the imported species in America. One might think that there was no doubt that Vanessa atalanta was indigenous to America, yet Harris asserts that it was introduced from Europe with the common nettle, and considering that Pieris rapa- was only introduced into Canada about 1S57, and now occurs abundantly even to the Rocky Mountains and Georgia, doing damage to the cabbage crop estimated at thousands of dollars annually, it is hard to prove the nationality of a species by its present distribution. So much for the specific forms, but how is it in the case of certain genera, such as Apatura ? The European species of this genus are few, and the several species in America are decidedly southern in their distribution, A. alieia occurring from Texas to Florida, A. celtis not farther north than Virginia, and so on. This undoubtedly requires some explanation other than that of boreal origin, especially as it is by no means an isolated case, and the only one I have to offer is the following. In the Isle of Wight there are found fossil land-shells more nearly allied to West Indian than any European forms, and from this and other evidence it seems certain that ages ago there was some connection between Southern-Europe and what is now the West India region (Southern Africa being at the time probably cut off by the submergence of the central region) and a similar fauna existed throughout. The glacial period destroyed this fauna in Europe almost entirely — Central Africa being under water it could not migrate southward, and the American connection was cut off. But a few species survived in the Mediterranean region, and were the origin of Apatura in Europe, and such shells as the Mediterranean Ttidora ferru- ginea, allied to common West Indian forms.* I am at present situated in a district, the Rocky Mountains of Colorado, peculiarly interesting from a geographical distribution point of view. The high mountain peaks, rising to over 14,000 feet, and continuous to the Arctic regions of British America, have been an easy pathway for the migration of boreal species southward, while a very different and un-European fauna occupies the lower regions, and mingles with the others on the mountain-side. Of the forty-eight species of Mollusca ascertained to occur in Colorado, no less than fifteen may be * And it is probable that the European genus ClausiHa mi- grated to the West Indian and South American region during the same period. considered specifically identical with British forms, and nine others are very closely allied, while the remainder belong to the peculiarly American fauna. The fifteen European species, besides being found in Colorado, have a wide distribution and are doubt- less native in America : J'itriua limpida (petluada) is found in Massachusetts and Manitoba ; and its variety angelicx, in Greenland ; Hyalina nitida occurs in Michigan and Massachusetts ; H. viridula (radta- tula) as far north as Alaska (W. H. Dall), and east as Mass. ; Conulus chersinus (fulvus) is found in Ontario and many other localities ; Helix pulchetla, var. costata, ranges to Anticosti Islands, and the type {hxvigata) is common in Canada ; Cochlicopasubcylin- drica [lubrica) is abundant from Alaska to Mass. ; Pupa marginata is found in Mass., where there also occurs its variety edentula ; Succinea ovalis (pfeiffen) is common in the eastern states and Canada ; Limnaa stagnalis occurs in Manitoba, Ohio, &c, and there is an American variety, speciosa, Zgk, of which I have seen English specimens collected in Yorkshire ; * Limiiaa palustris is universally abundant in the Eastern States and Canada, and very variable ; L. humilis (truneatuia, var.), is also generally dis- tributed and common ; Physa hypnorum occurs in Illinois, Ohio, Manitoba, &c. ; Planorbis parvus (glaber) is a well-known eastern and Canadian species ; as are also Pisidium abditum (pusillum) and P. variabilc {fontinale, subsp.). There are, however, several species of European mollusca which have been introduced into America, and must on no account be confounded with the boreal fauna, such as Helix Cantiana in Canada, and Li max maximus (cinereus) in the northern, and Helix terrains in the southern states. {To be continued.) THE WEATHER.f THIS is an excellent book which was greatly needed. For many years observers have been noting their observations of barometers and ther- mometers, yet the "great mass of these observations have been practically of but little use. A few years since we heard a great deal about " the gay science." Most persons have mistakenly con- sidered meteorology as the dismal science. Those who carefully peruse Mr. Abercromby's book will have no good excuse for still holding that opinion. The first three chapters, which form Tart I. of the book, are elementary, being weather-science and forecasting the weather. These chapters refer to * This variety differs from the type in its invariable tawny colour, its decided, almost regular striation, narrower aperture, outer lip less curved and not prominent, and its delicate clobely- adherent white columellar callus. f " A Popular Exposition of the Nature of Weather Changes from Day to Day," by the Hon. Ralph Abercromby, F.R.M.S., etc. etc. (London : Kegan Paul & Co.) HARDWICKE'S SCIENCE-GOSSIP. 27 observations of instruments and observations of the clouds. Part II. of the book is advanced, and contains fifteen chapters. The headings of a few of these chapters will give some idea of their contents : Wind and Calm, Heat and Cold, Squalls and Thunder- storms, Whirlwinds and Tornadoes, Types and Spells of Weather. After describing very clearly how isobars are formed, the author shows the relation of the velocity and direction of the wind to them, and the influence of different shapes of isobars in modifying the distri- bution of heat and cold from day to day in various parts of the world. Then the supposed relation between sunspots and rainfall is considered, and it is pretty clearly shown that no connection can be traced between them. For instance, in the year 1S72 — a year when there was a maximum of sun- spots — Buchan plotted the rainfall of Scotland, and found that while near Aberdeen the rainfall was seventy-five per cent, above the average, the amount of rain at Cape Wrath, about one hundred miles distant, was below the average. The author justly inquires why we should take the returns of one station more than another to compare with sun-spots, seeing that they should affect the whole world simultaneously. In a book on weather prediction so complete, it is curious to find no reference to the use of the Rain Band Spectroscope for predicting rain locally. Those who have tried the instrument know that it is of the highest value for this purpose. Writing now on the evening of December 4th, the barometer has been falling steadily since mid-day on the 1st instant — that is, successively night and day for three days. This morning, about 8 A.M., the clouds were very low and threatening, the atmosphere near the earth clear, so that hills six miles off were seen sharply defined ; every appearance would have induced one to believe that rain was imminent. On observing the spectrum with the spectroscope, I found an almost total absence of the rain band ; indeed, there was so little that only a well-trained eye could have detected it. No rain has fallen throughout the whole day. I have in my mind a case of positive prediction instead of negative, perhaps to many still more convincing. On the eve of a Bank Holiday recently, one of my friends, who had come into the country to stay with me for several days, said to me, "We are going to have a glorious day to-morrow." My reply was, " I am sorry to say we shall have a wet day to- morrow." "Nonsense," said my friend, who is something of a meteorologist, "the barometer has been rising for the last day or two, and we had a beautiful pink sunset." My answer was, " There is a strong rain band in the spectrum." The next morning, soon after 8 o'clock, it began to drizzle ; by 9 o'clock it was raining pretty fast, and it pouied almost continuously during the whole day. It would be easy to multiply such instances to almost any extent. Few persons are aware that a barometer rises very quickly an hour or two before a thunderstorm. This can seldom be observed, excepting on the diagrams taken with a self-registering barometer. A capital illustration is given in " Weather," by means of photography, from one of these diagrams. This sudden rise is mostly followed by two or three V's, resembling several reversed W's, with the V's be- coming smaller and smaller, thus — MM.> but the V's irregular in size. It is pretty well known to my friends that I sleep so soundly that no thunderstorm will wake me. On one occasion recently, at the breakfast table, I was told there had been a thunderstorm in the night. I immediately replied there had been two, about three hours apart. ' ' How can you know that, when they never wake you ? " was the inquiry. I told them that before I dressed I had consulted my self- registering barometer. As no one in the house had heard the two storms, my information was evidently doubted. Shortly afterwards a friend came in, who re- ferred to the two storms, and said they were about three hours apart. Considerations of space will not permit me to give an adequate idea of the matter in the volume, which consists of about five hundred pages, and contains nearly one hundred illustrations. It not only brings together all the knowledge we at present have on the subject of the weather, but it gives also the results of the author's original and unpublished researches, which are of great interest and value. Mr. Abereromby's book is indispensable to all who wish to understand the present position of applied meteorology, as exemplified in weather forecasts. John Browning. CHATS ABOUT ROTIFERS. (Ertemias tetrathrix.) THIS singular and rare rotiferon has been classified as belonging to the family Anurcedse, genus Ertemia (Gosse). The lorica is smooth, and shaped like a deep obconic wine-glass, of which the foot is represented by a long attenuated rigid bristle. Three similar bristles project from the front edge of the lorica. The centre bristle (the longest of the three frontal ones) springs from the dorsal margin, and is about one-fifth longer than the two side bristles. The head is projected a short distance from the mouth of the lorica, and crowned with a wreath of closely set vibratile cilia. C 2 28 HARDWICKE'S SCIENCE-GOSSIP. Its eye is large and of bright red colour, and is situated a short distance down from the mouth, and just above the mastax. The water vascular organs are conspicuous. The Fig. 13. — Ertemias tctrathrlx. tortuous tubes, with vibratile tags (three on each side), are distinctly discernible with a power of 500 diameters. The contractile vesicle is large, and situated below the digestive organs, at the contracted posterior end^of the lorica. It was in August, 18S5, that I had the good fortune to discover this remarkable creature in Stormont Loch, Blairgowrie. On examining a fragment of milfoil, which I had dredged from the bottom of the loch, in a zoophyte trough, with the water, I observed the E. tetrathrix busy nibbling at a colony stock of Codosiga umbel hit a. This beautifully pedicled and collared Flagellata, as well as a number of other forms of Pedicled Infusorians were thickly attached to the leaves of the milfoil, which seemed to form the chief article of food of the E. tetrathrix. It did not leave the colony of C. iimbellata until it had eaten most of the zooids from their foot-stalks, then left the colony stock a complete wreck, to attack a fine specimen of Acineta grandis. But the zooid quickly retired to the bottom of its cup-shaped lorica, and there baffled the efforts of the E. tetrathrix to extract it, which left the A. grandis little the worse for the assault. Its manner of swimming is unique. It swims quite as easily and gracefully backwards as forwards. It is the only species of the whole Rotifera I have met with that can voluntarily reverse its motion. It will swim forwards amongst the leaves of the plants and confervoid filaments, then shift its quarters by swimming backwards quite as swiftly as by the forward motion. I have seen many examples of this creature, both in the summer of 1885 and 1886. This voluntary reversing of the motion was a phe- nomenon in every individual specimen. Its egg is oblong, and after extrusion is fixed by a gelatinous matter to the posterior of the lorica on the ventral side, and there carried until hatched. Length from tip of the centre frontal bristle to the tip of posterior bristle, ^ of an inch. Length of lorica, ^ of an inch. John Hood, F.R.M.S. Dundee. SECTION-CUTTING. THE following remarks, supplementary to Mr. Underbill's admirable paper in the last issue, may be of some interest. In preparing specimens for mounting, the guiding principle in all the necessary manipulations should be to avoid any sudden change of density. For instance, it would not do to transfer such delicate tissue as that of a Medusa from 30 per cent, alcohol to 70 per cent, without first placing it for a few minutes in 50 per cent. As a rough rule, in passing a tissue which has been treated with some such hardening substance as corrosive sublimate up from water to absolute alcohol, the strength of the solution should be increased 10 per cent, each time, and the substance should average ten minutes in each, the time being slightly longer in the earlier stages. Corrosive sublimate is by far the best agent for first killing or fixing specimens, which HARDWICKE'S SCIENCE-GOSSIP. 29 may remain in a saturated solution for three or four hours. To kill animals in an expanded condition it may be used hot, and immediately replaced by cold solution. As an instance of its use, suppose one is dealing with the contents of a surface net, all animals of the most extreme delicacy. To the sea water in which these are swimming about add a small quantity of solution of ferric chloride, which will kill the organisms most effectually. They will now sink to the bottom and form a sediment, from which the sea water may be poured off. Fill up with saturated solution of corrosive sublimate,* and leave for three or four hours. Then thoroughly wash with distilled water, by decantation, until all traces of sublimate have disappeared, and pass up into 70 per cent, spirit in the way mentioned above. Specimens may be now labelled and laid aside, for they will remain unaltered for an apparently indefinite time. Now a few words as to staining. In the Cambridge Morphological Laboratory, all the preparations are stained before cutting, and the beautiful results ob- tained there quite dispose of the theory that staining in mass does not give definiteness of outline. There the block of tissue, or the animal, as the case may be, is left in an alum and calcic chloride solution of hema- toxylin for twenty-four hours. It is then washed as rapidly as possible in a solution of '25 per cent, nitric acid in 70 per cent, spirit. This dissolves out superfluous stain, removing it in part from those portions of the tissue which have no great attraction for it, and thus gives differential staining and great definiteness of outline. The time for leaving in the hematoxylin is not of vast importance ; all that is necessary is that the block should have time to become thoroughly filled with the stain. Definiteness of outline appears to be much more dependent on perfect dehydration than on staining. The nitric acid solution may be replaced by 70 per cent, spirit, this by 90, and this by absolute. By far the most delicate method of imbedding is the following. The stained specimen is left in the absolute alcohol until it is thoroughly permeated (a matter of a few minutes only) ; then, with a pipette, place a quantity of chloroform sufficient to cover the specimen, at the bottom of the small bottle in which it and the absolute alcohol already are, where it will form a lower stratum. The specimen will float in the upper layer of alcohol, and will only gradually sink into the chloroform, the alcohol with which the tissue is soaked being very slowly replaced. When this is accomplished, the upper stratum of alcohol and the chloroform may be drawn off with the pipette, and a little fresh chloroform added. Now shred some paraffin into the bottle, cork loosely, and leave for a short time at a temperature of about 300 C. The paraffin will be slowly dissolved by the chloro- * It is found best to make the solution with sea-water when jt is to be used for marine organisms. form, the density of the fluid equally slowly changing, and permeate the tissue. Raise the 'temperature to 6o° C, and the chloroform will be driven off, and when this is completed, as determined by smell, transfer to a larger quantity of melted paraffin, and imbed in the usual way. I am inclined to endorse Mr. Underwood's dictum, that the hardness of the paraffin should be varied according to the surrounding temperature. The temperature of the Cambridge laboratory is tolerably constant, from the method of heating, so I cannot speak from experience. There we use two kinds of paraffin, " hard " and "soft," the latter being of such a low melting-point that it can be moulded in the fingers at the ordinary temperature. The soft paraffin is used first, before passing into hard paraffin. It is also extremely important as an aid to obtaining " ribbons," serving, from its pliable nature, as a cement to unite the different sections together. To this end the little cubes are coated on only two sides with this soft paraffin, in the line in which the ribbons are intended to run. They are generally dipped bodily into some hard melted at a low temperature, and then the soft paraffin is carefully removed with a knife, except where wanted. I find it easiest myself to melt a little on the blade of an old scalpel, and apply as thin a layer as possible in that way, and on the two sides of the cube only on which it is needed. None of these statements are intended to traverse Mr. Underbill's remarks, since he was dealing only with insects, and I have had no experience of them. W. B. H. Cambridge, CHAPTERS ON COLOUR. By S. A. Notcutt, jun., B.A., B.Sc. No. II. T URNING to the mixture of pigments, we find results entirely different from those arrived at Red. Or. Yel. Gr?. Bl. Viol. Fig. 14.— Diagram of the Three Primary Colour Sensations (1, red ; 2, green ; 3, blue or violet) showing the extent to which they are affected by rays belonging to different parts of the spectrum. (Helmholtz.) ty mixing coloured lights. We know that blue and 3° HARDWICKE'S SCIENCE-GOSSIP. yellow light form white, whereas blue and yellow pigments form green. Now we have seen that the colour of a pigment is clue to the absorption which light undergoes in passing through the surface layers, and in being reflected back from the interior. We may represent the surface layer of a blue pigment by a piece of blue glass placed on white paper ; if we now place a piece of yellow glass over it, what will be the colour of the paper ? The blue glass transmits violet, blue, and green rays ; the yellow glass transmits green, yellow, orange, and red rays ; hence the only rays which the two glasses transmit in common are green rays. Therefore the paper will look green when covered by both glasses. This is a model of what takes place when a mixture of blue and yellow pigment is spread over a white surface ; green is the only colour which is not absorbed by either of them. Dove devised a simple piece of apparatus for comparing coloured light mixtures with pigment mixtures. He covered an aperture in a piece of card, half with one coloured glass and half with another, and caused the images of the two halves to overlap by examining the aperture through a piece of doubly-refracting spar. In the overlapping of the "ordinary" image of the one half by the "extra- ordinary " image of the other, a true mixture of the lights was obtained. He afterwards observed the colour of the two pieces of glass placed one over the other. Dove's results show that coloured light mixtures of red and green are yellow, whilst pigment mixtures of the same colours are black, or very dark green. Blue-green and dark purple light form a pale blue-green, whereas the same colours in pigments form a dark violet. In fact, pigments are always darkened by mixture on the palette, for by each successive mixture the absorption of some further rays is effected, and thus we have a continual process of subtraction ; each admixture is a stride towards blackness. There are two accepted theories of coloured vision — the Young - Helmholtz theory, and the Hering theory. The former, which was published by Young in 1802, supposes that there are three colour sensations which are called forth in different degrees by rays belonging to different regions of the spectrum. One of these sensations is a red sensation, which is excited most by certain red rays, but is nevertheless affected in a certain varying degree by other rays, the effect being less the farther the rays arc from the red, until in the blue region of the spectrum it is scarcely appreciable. Besides the fundamental red sensation, Young supposed there to be two other primary sensations, one being aroused to a maximum by certain green rays, and the other by certain blue or violet rays, but both, like the red sensation, being more or less affected by rays of every refrangibility. Helmholtz represented this varying capacity possessed by rays in different regions of the spectrum for awakening any one of the three sensations, by three curves (Fig. 14), the height of any point in any of the curves representing the extent to which the particular sensation is aroused by a ray belonging to that part of the spectrum. When the three sensations are aroused in equal proportions, we experience the sensation of white light ; this is shown to be the case by rotating a disc with red, green, and blue sectors on Maxwell's colour-top, when the whole will appear grey. We have seen that yellow and blue light, when mixed, makes a white or grey ; the reason for this is easily understood on referring to the diagram (Fig. 14), for there it is seen that a yellow ray affects both red and green primary sensations, whilst a blue ray affects both green and blue sensations, so that between the two we have the three factors required for giving rise to the sensation of white. By the diagram it is seen, too, that a yellow ray awakens the red and green sensations in about equal degrees. Now when a disc, half green and half red, is rotated, a dull yellow is the result ; when the disc is made up of more red than green, the tone of the combination approaches orange, as might be expected. In the same way, other intermediate colour sensations are produced, the resultant sensation produced by any ray or number of rays being determined by the relative extent to which each of the three primary or fundamental sensations is affected. According to this theory, black is the absence of all sensation. The Hering theory, which is more generally accepted by*1 physiologists, is partly based on the fact that we can pick out six different colours, each of which appears to us to be quite distinct from, and have nothing in common with, any other ; these six naturally fall into three pairs, which are black and white, green and red, blue and yellow. Each pair then comprises two correlative and complementary colours. The theory also depends on the existence of what are known as "visual substances." One such substance, which is of a purple colour, is found in portions of the retina of most eyes. This is called "visual purple," and is peculiar from the fact that, under the influence of light, it loses its colour, but regains it if kept in the dark. Hering's theory, on analogy with the phenomenon of visual purple, supposes there to be three such visual substances in the retina which are acted upon by light, and which in their changed chemical state in turn act on the fibres of the optic nerve, giving rise altogether to six colour sensa- tions. These substances are colourless, and are con- stantly undergoing either a constructive or destructive metabolism. One substance awakens the sensation of white when it is breaking up or undergoing dissimila- tion, and of black when it is being built up or undergoing assimilation. Similarly the second substance gives rise to a sensation of red or green, and the third substance to a yellow or blue sensation, according as dissimila- tion or assimilation prevails in the respective sub- HARD JVICXE'S SCIENCE- G OS SI P. 3r stances. Further these substances are such that in the red-green substance, red rays falling on it cause dis- similation, and green assimilation ; whilst in the yellow- blue substance yellow rays cause dissimilation, and blue assimilation ; but all rays alike arouse dissimila- tion in the white-black substance. Consequently, when yellow and blue light falls on the eye, dissimila- tion and assimilation in the yellow-blue substance is in equilibrium ; neither process goes on, and neither the sensation of yellow nor of blue is perceived, but since both rays act on the white-black substance, causing dissimilation, we perceive the sensation of white light. This has been shown above to be actually the case. An orange sensation is aroused by dissimilation of both the red-green and yellow-blue substances, purple by assimilation of the yellow-blue substance, and dissimi- lation of the red-green substance, and other inter- mediate colours by other variations in the dissimilation or assimilation of the substances. About the beginning of the present century it was discovered that many persons are born with a deficient perception of colour, being what is called " colour-blind," and it was noticed that this deficiency, though found more or less in one out of every eighteen men in England, was very rare in women, even when belonging to a family hereditarily colour-blind. Mr. Hugo Magnus supposes that our sense of colour has been developed during the last four or five thousand years, and that the savages before that period could only distinguish a dark from a light shade. He bases this theory of the evolution of colour on philo- logical researches, but the evident colour perception found in lower animals tends to contradict it. To be what is called "red-blind," is the commonest form of colour blindness. A person so afflicted fails to distinguish between rose-red and bluish-green : he sees little more than two colours in the spectrum, which he calls yellow and blue, the yellow including the red, orange, yellow and green spaces. He classes all these tints as yellows, though they are really greens, because yellow being more luminous than green, excites a green sensation even more than green does itself, hence yellows are more con- spicuous than greens to the colour-blind, but only by virtue of the green they contain. The extreme red, if at all faint, is invisible to a red-blind person. Maxwell found that, for a colour-blind person, it was only necessary to choose two colours (instead of three), and to combine them, by the aid of his discs, with the addition of black and white, in order to match any other colour ; whereas, for the normal eye, we have seen that the] combination of three colours, with black and white, was required. By comparing the colour equations obtained from his colour top, as adjusted by a colour-blind person, with the equations obtained when the experiment was conducted by a person of normal vision, Maxwell calculated the exact colour-sensation which was wanting in the colour-blind person. On the Young-Helmholtz theory, a colour-blind person lacks one of the primary colour sensations ; thus, if he is red-blind, his colour sensations are composed of the green and blue alone. On the Hering theory, a red-blind person lacks the red-green visual substance ; hence all his colour- sensations must be made up of blue and yellow. According to this theory, green-blindness cannot exist apart from red-blindness ; indeed, it has not been satisfactorily proved that this is ever really the case. The peripheral portions of the normal retina are red-blind, and these parts form a large and increasing proportion in cases of excessive tobacco-smoking. A certain shoemaker, named Harris, is recorded to have had scarcely any perception of colour at all, and must therefore have resembled Mr. Magnus's primeval savages. In gas-light, we are all in much the same condition as if we were partially violet colour-blind, and by the light of a sodium flame we can place ourselves in a condition somewhat like that of Harris. The light from this flame contains only yellow rays of a par- ticular wave length ; hence yellow objects look white, and all other colours look black, or a pale yellow, if they happen to reflect a modicum of yellow with their normal colour — in other words, we can only distin- guish light and shade effect. In all practical questions of colour, we find it necessary, not only to consider the colour of the body or surface itself, but also the colour of the adjacent medium, since the colour of the body will apparently change with alterations in the colour of such medium. This is known as Contrast. Thus, a red object looks brighter on a green than on a red surface. All contrast phenomena are the result of one of two distinct causes, being due either to fatigue of portions of the retina, or to fluctuations or error in our visual judgment. Effects produced by fatigue of part of the retina, or negative after-images, as they are generally called, have been so freely published in certain well- known advertisements, that it is scarcely necessary to mention them. After staring steadily at a bright red object and then turning the eyes on to a grey wall, we seem to see the object again, but its colour is green instead of red ; the reason being that the grey light reflected into the eye from the grey wall contains all the constituent rays of the spectrum, but the visual substance or nerves capable of awakening a red sensation having been wearied, the other colour sensations predominate, giving rise to a sensation of bluish-green, corresponding to that part of the retina which has been so wearied. The after image is necessarily of a complementary colour to the object, since whenever a colour is subtracted from white light the remaining colour is complementary to it. These experiments can be variously modified. By looking at a green object on a sheet of yellow paper and then removing the object, jwe see its after image 32 HARDWICKKS SCIENCE-GOSSIP. of an orange colour. Here the yellow paper reflects red, yellow, and green rays into the eyes ; but the sensation of green is worn out and we perceive only the red and yellow rays, and these we know give rise together to the sensation of orange. Or, placing a slip of black or green paper on red paper, so as to shield part of the retina from the red rays, then on removing the slip an image of it is seen on the red ground, the image being of a brighter and more intense red. The greatest contrast is obtained when the two colours are complementary to each other. Somewhat prolonged observation of such colours gives rise to a glimmering or lustrous appearance, which is the leading feature of another common advertisement. An experiment of Helmholtz furnishes an example of the deception to which our visual judgment is liable. He directed two beams of light, one ordinary daylight, and one candle- light, on to a white screen, A NEW PARASITIC COPEPOD. I LATE BY received from Mr. H. Chad wick, of Manchester, a specimen of Sabella, from the sandy shore at Beaumaris, N.W., which appeared to be infested with Copepoda. They were found at- tached to the gill filaments, to which they clung so tenaciously that it was difficult to remove them for examination without injuring the filament of the worm their host. The worm occurs in large numbers on the beach at Beaumaris, and several specimens taken were all found to be infested with the little Crustacean. Microscopical examination clearly shows it to belong to the genus Lichomolgus, family Sap- phirinidse (Thorell), but it differs in many important points from any hitherto known species. I propose to name it Lichomolpus sabella (Fig. 15). Its length is about T'5 inch, and with even a pocket lens it is readily distinguishable by its long narrow ovisacs and remarkable antennae. The body is Fig. 15- — Lichomolpus sahellce Q. and interposed an upright rod, so that two shadows were cast on the screen, one in each beam. After adjusting the lights till the shadows were of the same depth, he found that one appeared yellow, namely that cast in the beam of daylight, and the other blue. In this experiment the whole screen is really a pale yellow, being illuminated by a mixture of white light and yellow candle-light, but we accept it as white ; the consequence is that the shadow of the rod in the beam from the candle, which shadow is really pure white or grey since it is illuminated by daylight only, looks blue by comparison. Another experiment which depends on our mis- taken visual judgment consists in placing a small strip of grey paper on a brightly coloured paper and covering them with a sheet of tissue paper. The grey strip seen through the tissue paper appears of a complementary colour to the ground colour, and sometimes even more intense. This is a case of contrast between two greys, and the contrast effects are more marked than in the case of more intense colours. Fig. 16. — Posterior antenna; of Lichomolpus sabella. Fig. 17. — Anterior antenna;. Fig. iS. -Pair of Swimming Feet. elongated ; the first segment being about half the entire length of the cephalothorax which is of ovate form. The abdomen is composed of five joints : the first joint being in length equal to the remaining four joints, and proportionately broad. In the male, its lower angles are produced into two sharp narrow spines. Rostrum short and beak-shaped. Anterior antennas (Fig. 17) seven-jointed, the two basal joints much longer and broader than the rest, and roundly serrated on the outer margin. All the joints are clothed with strong spinous setae. Posterior antenna; (Fig. 16) four-jointed, and very powerful ; the second joint is provided with four small curved hooks placed longitudinally, and the apical segment has four large strong curved hooks, in shape much like shepherds' crooks. The posterior foot jaws vary in the two sexes. One of the first four pairs of swimming feet is shown in Fig. 18. The fifth pair are alike in both sexes, and are composed of one joint, with a long and short strong spinous seta at apex. The animal is of a greyish- brown colour. HARDWICKKS SCIENCE-GOSSIP. 33 Since the establishment of the Biological Labora- tory on Puffin Island, near to Beaumaris, under the directorship of Professor Herdman, systematic collec- tions of material are made by tow-net day and night, and several new and rare free-swimming copepoda nre already recorded ; but the above new parasitic species seemed of such special interest that I ventured 10 describe it in your pages. Isaac C. Thompson. Liverpool. GOSSIP ON CURRENT TOPICS. By W. Mattieu Williams, F.R.A.S., F.C.S. REMARKABLE ADULTERATION. — The following is from the columns of a popular periodical : "Materials, often largely ferruginous, are employed in the manufacture of glass for bottles, and the acids in wine act very powerfully upon these constituents, the consequence being that the liquid gets thoroughly impregnated with a solution of magnesia, or something very detrimental to the juice of the grape. When the wine thus affected, is drunk, it is found to be a sour, more or less nasty concoction." The chemistry of this is very wonderful. The impregnation of the wine with a solution of magnesia as a consequence of the action of its acid upon ferru- ginous materials presents a clear case of the transmu- tation of metals, and the souring of the wine by the using up of its acid is another blow to modern chemistry, one of its fundamental doctrines being that an acid cannot exert its solvent or combining energies without becoming proportionally neutralised. Electric Fishing. — One of Tiedmand's pictures in the Norwegian Summer Palace of the King of Sweden and Norway (Oscar's Hall, near Christiania), represents a peasant family spearing salmon at night in one of the fjords. A blazing fire of pine knots, or other resinous wood, is made on an overhanging cage at the prow of the boat. This light is an object of interest to the fish. While they are engaged in their investigations of the unusual phenomenon, the fatal blow is struck and they share the fate of Archi- medes. The " Scotsman " tells us that experiments are in progress in the Firth of Forth, in which the electric light is to be substituted for the glare of the wood fire as a means of piscatorial seduction. Electric lamps were sunk to a depth of forty or fifty fathoms, but the pressure of water was too great for the glass globes, which although very thick were broken by the pressure of the water. The account I have states that the glass was \ of an inch thick, but the size of the globes is not stated. An arc light of six thousand candle-power is described as having been used, and that further trials with stronger globes are to be made. If I dared to make a suggestion it would be to proceed more modestly at moderate depths. The Norwegians work on the surface for the lake trout and salmon. I have caught cod-fish as fast as I could haul them up by bottom fishing at five or six fathoms, and see no good reason whatever for trying such depths as forty or fifty. The Propagation of Cholera. —Certain Frenchmen have accused us of carrying cholera from India to Europe through the Suez Canal, in spite of the fact that it visited this part of the world long before the canal was made. The last visitation has been singularly fatal to this theory, according to which the cholera should follow the course of the East India ships, and therefore should make its European debut in London. Instead of this, London has escaped altogether, while Paris, and other large towns of France, Italy, &c, have suffered severely. Herr Pettenkofer referred to this in his address to the International Hygienic Congress at Vienna, and asked the question : " Why do the English, in spite of their enormous traffic with India, where cholera is never extinct, not transfer the disease to their own country?" He replies that England's immunity from cholera is not owing to quarantines and other expensive obstructions to international traffic, such as vainly exist in Italy, France, Spain, Russia, &c, but to superior cleanliness, and attention to the removal of sewage. He adds that the general statistics of the mortality of London show that our proverb "cleanliness is next to godliness" is well founded, and that hygienic piety has been rewarded by the heavens. Aluminium. — We may hope that, ere long, useful alloys of this metal will become cheaper. In spite of the difficulty of obtaining the metal itself, M. G. A. Faurie has devised an easy and inexpensive method of obtaining it in alloy with other metals. Two parts of finely powdered alumina with one of petroleum, or other hydrocarbon, are worked into a paste well kneaded, and one part of sulphuric acid added. When the mass becomes homogeneous, with a uniform yellow colour and begins to liberate sulphuric acid, it is put into a paper bag and raised to a good red heat in a crucible. The reduced pro- duct thus obtained is finely powdered and mixed with about its own weight of the metal (also in powder) with which it is to be alloyed and raised to a white heat in a crucible. We are told that on cooling after this, more or less rich grains of aluminium alloy will be found in the middle of a black metallic powder. I have not learned whether this black powder can be fully reduced and utilised by further treatment with carbon or hydro-carbon. If so the whole process is simple enough, and cheap enough, to afford good supplies. The Universal Solvent. — The old alchemists sought for three great arcana, the philosopher's stone, HARD WICKE ' S S CIENCE- G 0 SSIP. the elixir of life, and the universal solvent ; the latter being required to make gold drinkable and thus endue the body with its characteristic imperish- ability ; drinkable gold — aurum potabilc — being the theoretical composition of the elixir of life. Modern chemistry has done no more than alchemy towards revealing the first two arcana, but has accomplished the third. The universal solvent has been long known, but not until lately separated, and now cannot be retained simply because it attacks everything ; nothing can hold that which dissolves or destroys everything. This fury of the chemical world is the element fluorine ; it exists peacefully in company with calcium in fiuor spar and also in a few other compounds, but when isolated, as it recently has been by M. Henri Moissan, is a rabid gas that nothing can resist. It combines with all the metals, explosively with some, or if they are already combined with some other non-metallic element, it tears them from it and takes them to itself. In uniting with sodium, potassium, calcium, magnesium and aluminium, the metals become heated even to redness by the fervour of its embrace. Iron filings, slightly warmed, burst into brilliant scintillations when exposed to it, manganese the same. Even the noble metals, which even at a melting heat proudly resist the fascinations of oxygen, succumb to this chemical siren at moderate tempera- tures. Glass is devoured at once, and water ceases to be water by contact with this gas, which combining with its hydrogen, at the same moment forms the acrid glass-dissolving hydro-fluoric acid, and liberates ozone. Oyster Cultivation. — The victim of an ill-spent life, whose remorse on the remembrance of neglected opportunities, was lately pictured in "Punch," may yet find some consolation and opportunities of amendment. Though he may still regret that he did not eat more oysters in the irrevocable past when they ^were eightpence a dozen, the future is bright and hopeful. Oyster cultivation has been eminently successful in France. The exports in 1885 were 30 millions, and in 1887 they reached to about 52 millions, and the imports from Portugal to France have declined from 154,657 kilogrammes in 1S83 to 1500 kilogrammes in 1887. In Tasmania, Mr. Saville Kent is equally successful. In his report for 1886, presented to the Tasmanian parliament, he shows good reason for concluding that, by extending the system he has adopted in the government reserves, and by its adoption by private enterprise, the colony may ere long establish a lucrative oyster trade. Of course we may do the same in Britain, the classic fatherland of oysters, provided the enterprise is placed in the hands of such a man as Mr. Saville Kent, i.e. a naturalist who is not too much inflated with professional or other official dignity, nor endowed with too large a salary to work practically himself. A savant with a salary of ^1000 to ,£1250 per annum cannot descend to menial work ; one with three or four hundred is more likely to work for his bread, even though the work demands daily wading waist- deep, in salt water. Even the plodding Chinaman has beaten us in this branch of industry. He culti- vates oysters successfully, abundantly, and cheaply. Science in China. — The irresistible march of science is striding over even the ultra conservatism of China. Imperial sanction has been given to a profound innovation, to the introduction of mathe- matics and modern physics, also of civil and military engineering, and still more startling, of international law and the history of the outer barbarians. All of these have now become subjects of Chinese National Education in all the provinces of the empire, and of the examinations upon the results of which the social status and the whole career of the best men of the empire depend. If this is fully carried out, some of the weary, useless, and degrading rote work connected with the old-established examina- tions in the ancient Chinese classics, the exercises in prose and poetical composition, Chinese history, &c, must be pushed aside. When the thin end of this education wedge is fairly inserted, we may hope that the rotten old system will soon be reft asunder. On a people who have already acknow- ledged so fully the supremacy of the intellect ; whose old-established aristocracy is so largely built on the basis of intellectual competition, the effect of such reform must be enormous. It may even occur in the course of another generation that educational mission- aries from China will visit Oxford and Cambridge to promote the modernisation of our ancient Universities, basing their advocacy on the splendid results of the pioneer efforts successfully carried forward in the Celestial Empire. Science on Mont Blanc. — Some of the older accounts of electric displays on the summits of high mountains have been rather discredited of late ; even those of de Saussure have been treated rather dis- respectfully, chiefly, I suppose, because modern Alpine climbers have not confirmed them. My own experience among such climbers, especially in making an ascent of Mont Blanc so far back as the autumn of 1842, explains the negative results. The whole business of such climbing consists in reaching a certain peak, resting thereon for a few minutes to drink champagne or Kirschwasser, and take breath, then galloping and glissading down with helter- skelter pell-mell rapidity. Deliberate observation of anything beyond the reading of a barometer is out of the question in such expeditions. Last summer, however, MM. J. Vallot and Richard did some genuine work on the summit of Mont Blanc, where they erected a tent and remained for three days and three nights with the ability and appliances for making meteorological and other observations. One HARD WICKE' S SCIENCE- G OS SIP. 35 of these I may quote, as it confirms some of the old and disreputed statements above alluded to. After a severe storm that imperilled their tent, M. Vallot on going out at about 9 P.M. found himself an in- teresting object. His clothes and his head were in the condition of the prime conductor of a working electrical machine. The rock on which he stood was in an opposite electric state to the mist around him, and his body thus became a crepitating sparkling discharger. ASTRONOMY AND METEOROLOGY. By John Browning, F.R.A.S. ON February the nth, there will be a partial eclipse of the sun, not visible at Greenwich. On February the 20th, Aldebaran will be very close to the moon. Mercury will be an evening star in the west, near the horizon, about an hour after sunset. Venus will be a morning star throughout the month. Mars will be in Virgo. Jupiter will be visible early in the morning in Scorpio. Rising, Southing, and Setting of the Principal Planets at interz'als of Seven Days in February. Rises. Souths. Sets. D. h. m. h. m. h. m. 5 8 9M i 6a 6 3A 12 7 5SM 1 19A 6 43A Mercury 5 . 19 7 3°M 1 17A 7 44* ' 26 6 54M 0 50A 6 46A / 5 5 29M 9 32M 1 35* Venus $ . . I 12 5 36m 9 41M 1 46A ' 19 5 38m 9 49M 2 OA 26 5 3§M 9 58m 2 i8a t 5 n 14A 4 41 M IO 5M Mars & . . j 12 10 56A 4 20M 9 41M 19 10 34A 3 58m 9 1 8m ' 26 IO I2A 3 33M 8 51M ( 5 2 49M 7 6m n 23M Jupiter %. .1 12 2 26il 6 42M 10 58M 19 2 3M 6 i8m 10 33M ' 26 I 39M 5 53M IO 7M ( 5 3 21A 11 15A 7 14M Saturn T?. J 12 2 51A IO 46 A 6 45M 19 2 19A 10 i6a 6 17M 26 1 50A 9 47A 5 48m Meteorology. — There being nothing of popular interest to record as regards Astronomy this month, I shall devote my space to a summary of the Meteor- ology of 1887. From the observations published in the daily weather report of the Meteorological Office, it appears that the temperature rose in July to a maximum of 88 deg. and fell to a minimum'of 15 deg. in January, which was the lowest reading observed for six years. The extreme range for the year of 73 deg., was the largest observed for many years. The mean temperature was below the average in every month, excepting June and July, and very considerably below the average in March, April, May, September, and October. The mean tempera- ture for the year showed a deficiency of 2 deg., and, with the exception of 1879, was the coldest that we have experienced for at least twenty-five years. Respecting rainfall, we find that rain fell on twenty- four days fewer than the average, and that the amount which fell was less than the average in every month, excepting August and November. In January, June, and July, it was about half, and in October it was less than half, while in February it was only one-third of the average. The total rainfall for the year was 20 per cent, below the average. For some of the midland and south- western counties, and for parts of Ireland, the year 1887 was the driest on record. In the neighbourhood of London the number of warm and very warm days was the smallest we have experienced for eight years. The number of cool days exceeded any year since 1879, and to find an equally great number of frosty nights we must go back at least twenty-five years. Owing to the deficient temperature- having occurred mostly in the spring and summer months, the death-rate from diseases of the respiratory organs was not abnormally low. The two features of the most striking interest in the meteorology of last winter were the great gale on the 8th and 9th of December, 1886, and the heavy snowstorms in the south of England on the 26th of the same month. During the gale on the 9th of December, the barometer sank in London to 28*30, the lowest level recorded in the Metropolis for forty- five years. Over the greater part of England, including London, the spring was the coldest on record. The summer of 1887 was remarkable for its bril- liancy. From the 5tft °f June to the middle of August there was an almost unprecedented drought. Long spells of heat were experienced in London during July and August. The amount of bright sunshine recorded at Greenwich was greater than in most years, and nearly double that of the summer of 1879. The autumn of 18S7 was cold, changeable and unsettled. Snow fell as early as the loth of October. The mean temperature was greatly below the average in England, but not in Scotland. The rainfall in the autumn was less than the average in most places, the deficiency in London being 7 per cent. The present winter, so far, has been very change- able and unsettled. There have been no very severe 36 HA RD WICKE'S SCIENCE- G 0SS1P. frosts in England, but on the Continent the cold just at the end of December has been intense. Since then we have had high winds, rains, and several alternations of temperature. At the Royal Observatory, Greenwich, the highest reading of the barometer for the week ending 17th December, was 29 '95 in. on Monday morning, and the lowest 29*13 in. on Thursday morning. The mean temperature of the air was 40*7 cleg., and 0*2 deg. above the average. The general direc- tion of the wind was south-westerly. Rain fell on six days of the week, to the aggregate amount of o*8i of an inch. The duration of registered bright sunshine in the week was 5 "8 hours against 5*3 hours at Glynde-place, Lewes. For the week ending 24th December, the lowest reading of the barometer was 29*34 in. on Monday morning, and the highest 29*88 in. on Thursday evening. The mean temperature of the air was 34*9 deg., and 4*7 deg. below the average. The general direction of the wind was north-westerly. Rain or melted snow was measured on four days of the week, to the aggregate amount of 0*17 of an inch. The duration of registered bright sunshine in the week was 1*9 hour, against 5*7 hours at Glynde- place, Lewes. For the week ending 31st December, the lowest reading of the barometer was 29*65 in. on Sunday evening, and the highest 30*07 in. on Friday evening. The mean temperature of the air was 32*1 deg., and 6*7 deg. below the average. The general direction of the wind was north. Rain fell on two days of the week, to the aggregate amount of 0*02 of an inch. The duration of registered bright sunshine in the week was 6 * 2 hours, against 1 1 * 1 hours at Glynde Place, Lewes. For the week ending 7th January, 1888, the lowest reading of the barometer was 29*15 in. on Monday afternoon, and the highest 30*26 in. at the end of the week. The mean temperature of the air was 40*2 deg., and 2*4 deg. above the average. The general direction of the wind was southerly. Rain fell on five days of the week, to the aggregate amount of 0*40 of an inch. The duration of registered bright sunshine in the week was 4*1 hours, against 4*5 hours at Glynde-place, Lewes. In February the temperature remains as in January near the Land's End, but North and East it is higher than in January, the average in London being nearly 2 deg. warmer. The average for the Land's End is 45 deg. ; for Devonport, 44 deg. ; Exeter, 43 * Ports- mouth, 42 deg. ; on a line drawn from Liverpool to London, 41 deg. ; and from the Sol way Firth to the East Coast at Norfolk and Suffolk 40 deg. The average rainfall for February is 1 inch on the East Coast, 2 inches on the South Coast, 3 inches on the greater part of the West Coast, and from 4 to 5 inches inland at Dartmoor, and in some parts of North Wales. I UNRECORDED DAPHNIA. SEND herewith a drawing of a Daphnia— found in the autumn of last year in a pond near Rye- Fig, ig. — Side view of Daphnia. Fig. 20. — Front view of Daphnia. Size, inch. House, of which I can find no mention in any of the HARD WICKE'S SCIENCE- G OSSIP. 37 books available to me, and which I think is un- recorded, at least in England — in the hope that some one better acquainted with this family may be able to name it. It will be observed that it has five filaments to each of the branches of the inferior or swimming antenna, and belongs therefore probably to a genus other than Daphnia. The superior antennae are long and ap- parently three-jointed ; the large single eye is accompanied by a black spot in front of it. Its mode of swimming is in long jerks, resembling more Tida crystalina in this respect than the common Daphnia. The internal organs appear to be normal. I have seen a number of individuals, but they were by no means plentiful. Size of body, T'B inch. C. ROUSSELET. SCIENCE-GOSSIP. A COMPLETE history of the Vertebrates of Leices- tershire and Rutlandshire will shortly appear, compiled from notes by Dr. Macaulay and others, and edited by Mr. Montague Browne, of the Leicester Museum. The Rutlandshire part will be edited by Lord Gainsborough. The Rev. A. C. Waghorne is publishing a series of excellent papers in "The Colonist" on "The Berries and Fruits of Newfoundland." Mr. Francis Galton has delivered three im- portant lectures at South Kensington on " Heredity and Nurture." A lecture was recently delivered by Mr. W. August Carter, of the National Fish Culture Associ- ation, at Foresters' Hall, Forest Hill, upon the "Denizens of the Aqueous Kingdom." After com- paring the habits and instincts of fish with terrestrial animals, the lecturer commented upon the question of migration, and considered that we ought not to attribute the cause of fishing grounds being depleted to the temporary absence of migratory fish. The barren condition of many fishing grounds was due to over-fishing and the devastation wrought in reaping the products of the ocean. The question of migration was a mysterious one, but probably it would be found that fish merely alternated their movements between their spawning and feeding grounds. He considered it was high time that the Government supported a system of fish culture, not only in regard to fluviatile but also marine forms ; also a system for providing technical education to fishermen. Dr. F. P. Venables has given in the " Chemical News," the results of a series of experiments on the degree of dilution at which different substances can be tasted. Known weights of the substances were dissolved in water, diluted to known extents with water, and one cubic centimetre of the solution was tasted by each of two persons. The results were : — sugar, three ten-thousandths of a gramme barely tasted ; salt, one-thousandth barely tasted ; tannin, two ten-thousandths tasted, one ten-thousandth failed to taste ; hydrochloric acid, one ten-thousandth barely tasted ; strychnine, one two-millionth barely tasted. Thus the sensitiveness of taste is inferior to that of smell. The monks of St. Bernard have established the highest-lying telephone connection in Europe, in order to facilitate their famous work of charity. Their well-known hospice is now in telephonic communication with the towns of Proz and St. Pierre in Switzerland and those of Fontine and St. Remy, on the Italian side of the mountain. The borings now being carried on in the Nile Delta by the Royal Society have been temporarily stopped by the breaking of the pipe. The depth reached is over 324 ft., but no solid rock has been arrived at. Experiments have been recently made in St. Petersburg with the idea of slaughtering cattle by electricity, the results of which have been highly satisfactory — death being in all cases instantaneous. The Selborne Society has issued the first monthly part of the " Selborne Magazine," as the accredited organ of their society. We are sorry to record the death of Professor Balfour Stewart, of Victoria University, Manchester, at the comparatively early age of 59. The name of the "Youth Library and Scientific Society " his been changed to that of the " Universal Society of Science, Literature, and Art," and its official organ henceforth will be the "Junior Review," a copy of which we have received, and which promises well. The fifth annual meeting was held on the 10th ult. at Exeter Hall. We wish the Society every deserved success. A General Meeting of the " Practical Naturalists' Society " was lately held in London, where the Society was judiciously strengthened by the recon- struction of some departments. Full details of the meeting appear in the pages of the " Garner " for January. Peculiar Sunflowers. — No. 1 had its outer row of florets, tubular instead of ligulate ; each floret was about one inch long, with five teeth and a slit about half-way down one side. The ilower head of No. 2 had its centre occupied by a number of involucral bracts, with a ring of ligulate florets surrounding them, giving the flower a most curious appearance. — J. E. C. 33 HARD WICKE' S S CIENCE- G OSSIP. MICROSCOPY. The "Journal of Morphology." — It is singular how long American morphologists have been content to send many of their memoirs to England for publi- cation, from the want of an authoritative journal, dealing specially with Morphology, in their own country. Several such magazines have been started from time to time in the United States, which were fondly expected to play the same part there that the " Quarterly Journal of Microscopical Science " does in England, but all lamentably failed. Their editors did not succeed in gaining the confidence and support of the best American workers. A new venture has just appeared, under the title of the "Journal of Morphology," and the first number is now before us. It is edited by Mr. L. O. Whitman, the prestige of whose name will go far to ensure its success, and the seven memoirs included in its first issue are remarkable both for the importance of the subjects and from the fact, that they are contributed by men who stand in the first rank of American science. The plates and style of printing are of that high class familiar to readers of the English journal. The English agent is Mr. W. P. Collins, 157 Great Portland Street, London. Microscopical Society of Calcutta. — An in- teresting meeting of the Microscopical Society of Calcutta was held on the 5th of December last, when Mr. H. H. Anderson read a paper on a new Infu- sorian discovered by him. It is parasitic in the alimentary canal of JEolosoma chlorosHctum, W. M. mss., and has been named Anoplophrya ccolosomaiis. In some cases seven or eight of the parasites have been found in a single worm. The Infusorian some- times disintegrates while under observation in a curious way, releasing a swarm of ciliated cells. It divides by fusion, and in some instances two septa have formed in a single organism. At the same meeting, Mr. E. J. Jones, A.R.S.M., described some nodular stones which have recently been dredged up off Colombo, in the island of Ceylon, from a depth of 625 fathoms. They possess a specific gravity of 3*77, and it was supposed their great weight was due to an excess of manganese, as was the case in the nodules of the "Challenger" expedition. Only a small trace of manganese is, however, present ; but as much as 75 per cent, of sulphate of barium is found. Sections made for microscopic examination indicate a volcanic origin. The splierulites show black crosses, with the nicols crossed ; and when the prisms are rotated, the orientation of the crosses re- mains fixed. The sections also show indications of foraminiferce, though from the crystalline texture of the nodules, it is clear they have been subjected to great heat. — A. E. Simmons. ZOOLOGY. Scarcity of V. Atalanta in 1887. — My ex- perience with regard to the scarcity of V. atalanta during the past season coincides exactly with that of your correspondent, R. B. P. In the country round Malvern, where I spent August and September, and where Atalanta is usually common enough, I only saw one specimen at the end of August. — A. G. Tan shy. Odostomias at Herm. — During a visit to the Channel Isles in September last, I took the follow- ing species of Odostomia at Herm : — O. unidentata, Mont., of occasional occurrence ; O. dolioliformis, Jeff., a single specimen ; O. spiralis, Mont., com- mon ; O. fcnestrata, Forbes, one beautiful specimen — this species is recorded for Jersey only by Dr. Jeffreys ; O. scalaris, Ph., of occasional occurrence ; O. lac tea, L., common ; O. acicula, Ph., rare. I may also mention amongst the Rissoids that occurred to me this year in Herm, the following : striatnla, Mont., lactca, Mich., cancellata, da C, calathus, F. and H., reticulata, Mont., Zetlandica, Mont., violacea, Des M., costulata, Aid., punctura, Mont., and semistriata, Mont. — B. Tomlin. Insects, &c, at Gibraltar. — Mr. James J. Walker contributed to the " Entomologists' Magazine " a paper on " A Year's Insect-Hunting at Gibraltar ; " it appears that the insects that swarm about the rock are of wonderful interest. There is scarcely a day throughout the year on which butterflies may not be found, and Mr. Walker enumerates fifty-five species for the limited district, thirty of which have occurred on the rock itself. He has found nine hundred species of beetles, and is daily adding to the number. The rock is the sole European locality in which the Barbary ape is found in a wild state. These animals, reduced a few years ago to less than a dozen indi- viduals, have of late greatly increased in numbers, and, being strictly protected, are very bold and fearless. The fig-trees in the gardens suffer so much from their depredations when the fruit is ripening that it is found necessary to employ men to scare them away. The Barbary partridge, though numerous on the rock, as well as on the opposite African coast, is, like the monkey, found nowhere else on the European continent. Mr. William Burgess, proprietor of the Midland Counties Fish Culture Establishment, states that a pond constructed by him last March, measuring fifty feet by thirty feet, which was entirely isolated from other similar ponds, was shortly after its formation found to be populated with trout fry in their alevin stao-e. No fish of any kind had been placed in the pond, and none could have entered it, the inlet and HARD WICKE ' S S CIE NCE - G 0 SSIP. 39 outlet being blocked with perforated zinc of a very fine mesh. The soil of the pond in question was excavated from a brook where trout must have previously spawned, and the ova although buried in mud and flung heedlessly about, survived, and the fry came to life when water had been let into the pond. This is another proof of the enduring capacity of Salmonidge ova. Autumnal Migration of Birds. — An article appears in the January number of the " Zoologist," by Mr. Allan Ellison, on the "Autumnal Migration of Birds in Ireland." Mr. Ellison says that the migration movement of last autumn in Ireland was in all respects a most exceptional one. Some of the migrants appeared unusually early, and all in much larger numbers than he had ever before observed. On October 8th he saw the first flocks, both starlings and redwings. On the same day, and for about a week after, immense numbers of golden plovers were passing over, flying towards the west and south-west in large V-shaped strings. This was about the usual time for starlings and redwings, but early for golden plover. On the nth, again, both redwings and starlings were constantly passing. On the 16th, he observed a great host of fieldfares, many thousands in number, winging their way across the sky towards the south-west. From October 17th to the beginning of November, the starling migration was at its height, the flocks being much larger and more numerous than he had ever observed in former years. He saw within a quarter of an hour on the afternoon of the 1 8th. At 4 p.m. on the 22nd the largest flock he ever saw passed over. It was in the form of a column, perhaps nearly a mile long, and must have numbered thousands, spanning the sky from horizon to horizon, for more than half a minute, and was followed in a short time by two smaller flocks. All the latter part of October skylarks were from time to time flying over, generally large straggling flocks or scattered individuals, flying nearly out of sight, but their call- note being distinctly audible. Mr. Ellison hopes that those who are favourably situated for observing the arrival of winter birds will report whether they have noticed a corresponding abundance of migrants this season. ANIMAL PSYCHOLOGY. Mister Pup. — She is a sftiid lady of seven years, but such is her name, is a half-bred Bedlington, of undeniable mental acuteness, which is proved, I think, by the following acquired habit. She always drinks from a saucer placed beneath the stone filter in a corner of the dining-room. Finding the saucer frequently empty, she has learned to turn the tap for herself by licking vigorously. She has taught another dog the same habit, but, unfortunately, they forget to turn the water off when thirst is assuaged ; con- sequently a pool too often stands on the carpet. A new and firm tap has had to be placed on the filter, much to Mister Pup's indignation and wrath. Shag and Gull. — Mr. Winwood Reade, in his " Martyrdom of Man," speaking of morality in animals, says : " If they have human virtues, they also certainly have human vices." The following incident, vouched for by a scientific friend of mine in Guernsey, shows that some of our feathered friends are about on a par with humanity, in, at least, the matter of " lex talionis." Near Guernsey harbour, a few days ago, a shag (Cormoranus cristatus) was diving for smelts, which, when captured, he came to the surface to dispose of. Having caught one that was too large to bolt, he cut it in halves, and while he was swallowing the first of these, a gull, that was swimming near by, "annexed" the other. The shag, after a moment's deliberation, commenced proceedings in swordfish versus whale fashion ; taking a dive, he came up with great force below the gull, giving it such a thrust with his strong bill as to knock it right out of the water, following up the onslaught by seizing the gull's leg, and for some seconds striving hard to drag the loudly expostulating, or, perhaps, apologising, culprit under the surface. Instinct ? — J. Sine!. BOTANY. Campanula glomerata and Gentiana cam- pestris. — The note by R. B. P. on these plants on page 21 of January Science-Gossip, must be my excuse for mentioning the fact, that the former plant is frequent in S. Beds, on the chalk hills, and often assumes the unifloral diminutive form described by your correspondent as characterising it on Beachy Head. The Gentiana campestris does not appear to grow in S. Beds, at least, I have searched for it diligently for six or seven years, but without success. Gentiana amarella is abundant here, and it frequently occurs with tetramerous flowers, so that at first sight it is easy to mistake it for G. campestris : in fact, the numerical arrangement of the floral organs is of little use in distinguishing the species, the only safe guide being the deeply-divided calyx of the latter. Not having ever found G. campestris, an exchange of specimens with R. B. P. would be acceptable to J. Saunders, Rothesay Road, Luton. Flowers and Fruits.— The question put by A. G. Tansley is one which has engaged my thoughts a good deal, as I have always believed that botanists had not been happy in their choice of words to describe the relations between foliar and floral organs. On reading that a leaf is much more highly organised than a petal, it is well to remember that a petal is not an essential organ ; that is, not an organ of repro- 4o HARD IV J CKE ' S S CIENCE- G 0 SSIP. duction. That the uppermost leaves on a stem should be starved, aborted, or degraded is not indeed what one would expect, considering that leaves are organs of nutrition each of which makes the plant that bears it richer as it grows. Look at a young plant of the scarlet-runner, the second pair of leaves is larger than the first. So it is with peas and other plants raised from seed, that the leaves are larger as they are in- creased in number, the later leaves having an ad- vantage in the nutriment elaborated by those that came before. We might therefore expect that a plant having no definite limit to its power of growth, an exogenous tree, would go on lengthening upwards till it should reach the height at which its leaves would be starved by reason of the rarefaction of the atmosphere. Such however is not found to be the case. The length of a branch bearing leaves is evidently determined by some other principle than the nourishment which the leaves afford and which is not all spent in provision for the leaves which come immediately after, but stored up in bulb, come, tuber or rhizome, or it may be in a woody stem. Thus it is that the upper leaves upon a stem may be starved, aborted, or degraded at the same time that the plant is laying up a store of nourishment. This procedure of a plant may be compared to the conduct of a man whose bodily strength is exhausted by work till he is no longer able to stand up long enough to earn fourpence by manual labour, but who has laid up so much of what he had already earned as to have capital at his disposal which he may use to gain a profit. By such an expenditure of capital, a plant produces flowers, fruit, and seed, as we may some- times notice in an old apple-tree covered with blossom and afterwards with fruit though so weak from age that it can hardly form a leafy twig as long as your little finger. — JoJui Gibbs. Dielytra spectabilis. — As the naturalisation of foreign species ought always to be placed on record, it may be mentioned that near Coates, Sussex, this pretty flower, doubtless a garden outcast, has become well established during the last few years in woods in the neighbourhood, and will doubtless attract the attention of future observers. It may also be noted that, both as to foliage and flowers, it has so deterio- rated that it has a very different aspect from the cultivated plant. Like other of the Fumariacere, such as Corydalis hitca, it may possibly become a recognised alien in our flora. — F. II. Arnold. Raphides. — At a recent meeting of the Jena Naturalists' Society, Frof. Saahl read a paper on the meaning of those excreta of plants called Raphides, i.e. crystalline needles often found in the cells in large quantity. From experiment he inferred that they were a protection to plants against being eaten by animals. Many animals avoid plants with raphides, or eat them reluctantly ; and some animal, e.g. snail species, in eating plants that have raphides select those parts that are without the crystals. Many plants held for poisonous, e.g. Arum maculatum, owe their burning taste simply to the very numerous raphides, which, forced out of their cells, enter the tongue and palate. The juice obtained by filtration has quite a mild taste. GEOLOGY, &c. The Discovery of a Gigantic Turtle by Dr. Donnezan. — This specimen was found, with numer- ous other fossils, in the middle Pliocene of Perpignan during the recent excavations connected with the erection of the fortress of Serrat in the Eastern Pyrenees. The carapace, 1*20 metre long, was ex- tracted with great difficulty from the hard rock in which it was completely imbedded, the innumerable fragments being carefully put together by Dr. Donnezan, by means of about a thousand brackets. This turtle, which he has presented to the Paris Museum, considerably exceeds its living congeners, being equal in size to the T. gra?ididier, a sub-fossil species found in Madagascar. Its survival down to the close of the Middle Pliocene is important for the study of the glacial period, tending to show that the South of France even then still enjoyed a warm climate. The Correlation of some of the Eocene Strata in the Tertiary Basins of England, Belgium, and the North of France. — Prof. Joseph Trestwich has recently read a paper on this subject before the Geological Society. Although the relations of the several series have been for the most part established, there are still differences of opinion as to the exact relation of the Sable de Bracheux and of the Soissonnais to the English series ; of the Oldhaven Beds to the Woolwich series ; and of the London Clay and Lower and Upper Bagshots to equivalent strata in the Paris basin. The author referred to the usual classification of the Eocene Series, and proceeded to deal with each group in ascending order. The Calcaire de Mons is not represented in England, but may be in France by the Strontianiferous marls of Meudon. It contains a rich molluscan fauna, including 300 species of Gasteropods, many of which are peculiar, but all the genera are Tertiary forms. The Heersian are beds of local occurrence, and Prof. Prestwich sees no good reason for separating them from the Lower Landenian or Thanet Sands. He gave reasons for excluding the Sands of Bracheux from this group. Out of twenty-eight Pegwell-bay species, ten are common to the Lower Landenian, and five to the Bracheux Sands, which present a marked analogy with the Woolwich Series. These Sands of Bracheux are replaced in the neighbourhood of Paris HARDWICKE'S SCIENCE-GOSSIP. 4i by red and mottled clays. Out of forty-five species at Beauvais only six are common to the Thanet Sands and ten to the Woolwich Series. Out of seventy- five species in the Woolwich and Reading Beds nineteen occur in the Bracheux Beds, if we add to these latter the Sands of Chalons-sur-Vesles. Respecting the Basement Bed of the London Clay (Oldhaven Beds in part), Prof. Prestwich would exclude the Sundridge and Charlton fossils, which should be placed on a level with the Upper Marine Beds of Woolwich. He allowed that the former were deposited on an eroded surface, but this involves no real unconformity, whilst the palceontological evidence is in favour of this view, since out of fifty- seven species in the Sundridge and associated beds, only sixteen are common to the London Clay. He therefore objected to the quadruple division. Either the Oldhaven should go with the Woolwich or with the Basement Bed. He admitted that the term " Basement Bed" is objectionable, and preferred Mr. Whitaker's term for the series, as he would limit it. The Lower Bagshot Sands, Prof. Prestwich would call "London Sands," whose Belgian equivalent is the Upper Ypresian, and the French the Sands of Cuise-la-Motte, forming the uppermost series of the Lower Eocene. A group of fossils has been discovered in the Upper Ypresian sands of Belgium, which leaves no doubt of their being of Lower Eocene age, and consequently the Lower Bagshots must be placed upon the same horizon. There is no separating line of erosion between the London Clay and the Lower Bagshots, the upper part of the former is sandy, and the lower part of the latter frequently argillaceous. Similarly no definite line can be drawn between the Upper and Lower Ypresian ; but in both countries this series is separated from overlying beds by a well-marked line of erosion. So also in France the base of the Calcaire Grossier (Bracklesham Beds) is a pebbly 'greensand resting on an eroded surface of the Sands of the Cuise-de-la- Motte. In Belgium, in Whitecliff Bay, and in the Bagshot district the Upper Eocene rests upon an eroded surface of the Lower Eocene. NOTES AND QUERIES. Green Tree Frogs. — While staying at Mentone some eighteen months ago, I sent a parcel, containing twelve or fourteen green tree-frogs, to a friend in Brighton who wished to see some, as he had heard a great deal about them ; but, on their arrival, not knowing what to do, as they were so lively after their journey, he released some in the garden among the shrubs, but from that moment he saw no more of them ; the remainder he gave to two friends to keep in their greenhouses. A few weeks after, I happened to be at his house, when he told me that he had searched everywhere, but cDuld find no signs of the frogs which he had liberated, and in the course of conversation informed me that his next-door neigh- bour had a duck, which quacked in a very peculiar manner, different to any that he had ever heard before. On his mentioning this, I suspected that, instead of a duck, it was one of the frogs which had clambered over the wall, and taken up his quarters there. Later on, my attention was called to the sound, which, on being localised, was found to proceed from the upper part of a large bush growing against the wall, but no frog could be found, the foliage being so thick. During the summer months, the frogs strayed from garden to garden of an evening after sunset, or whenever it came on to rain : one would commence croaking, and directly afterwards another would answer from perhaps six or eight gardens away, and then a third, until it almost reminded me of an evening in the Riviera. When the cold weather commenced, they evidently perished, for they were heard no more. Wishing to study a little the habits of these most interesting creatures, I obtained (some sixteen months ago) eleven from the same locality, which I placed in a small fern-case ; they seemed to like their quarters much, especially one corner which I arranged to form a pool of mud ; but, as regards feeding them, they disposed of blow-flies, houseflies, spiders, or, in fact, any insect which showed signs of life — dead ones they would never touch — in such quantities that they seemed to be never satisfied, their favourite diet apparently being blow-flies, bees or wasps, the stings not disturbing them in the least, and the more they buzz the better they like them. During the winter three of the smallest died, and the surviving eight, evidently owing to the liberal supply of food, have grown considerably. It is astonishing, considering the size of them, what a quantity they can manage to eat or rather swallow. I have seen them tackle and successfully put out of sight, three and four large cockroaches, legs, elytra, and all, and then quietly retire to some obscure corner to go to sleep for a week or ten days, and digest their hearty meal. Since their confinement, they have become very tame, and afford an endless source of amusement to my friends, who, when they happen to hear one croak, express their astonishment that such small creatures should be able to produce a sound almost as loud as a duck. The approach of winter is already very perceptible in their behaviour ; they are very sleepy, and have but little appetite for the dainties with which I tempt them, soon they will search out secluded corners, and prepare for their winter sleep.— M. R. The Term " Rudimentary " as used ey Darwin. — The writer of the article on this subject resents in strong terms the use which Mr. Darwin makes of the term "rudimentary" in his " Descent of Man," as an insult to the human race. I cannot help thinking that this is rather far fetched, and surely it is far better, and requires no very great stretch of generosity or magnanimity to look in this case more to the spirit than the letter. No one of 42 HA RD WICKE'S SCIENCE- G OS SIP. course will deny that the strict and literal sense of the word " rudimentary " is "rude and unwrought" or undeveloped, but it is equally certain that Darwin would have been the last man in the world to tell us that our organs have never reached perfection. So far from leaving me " impressed with the appalling fact that, after all, our much-admired human form, with its boasted superiority, is but a bundle of rudimentary organs, which have never reached perfection," the works of Darwin teach me in a most unmistakable manner that we are so wonderfully made that our organs are in the highest state of perfection for the existing circumstances, and that we are so constructed that when the conditions alter, our organs do likewise, and thus we remain perfectly adapted to our surroundings, and this should immeasurably increase one's awe of the Power which, in the first instance, created a creature at once suited, admirably suited, to the conditions by which our primaeval ancestors wrere surrounded, provided with the means of bettering his condition and of raising himself to a high state of civilisation, and at the same time enabled to adapt his organs to this higher environment. Surrounded as they were by all sorts of wild animals with whom they were compelled to fight for life and for food, it was essential that the senses of sight, smell, and hearing, should be highly developed in our ancestors ; but in this nineteenth century we no longer require such keen perception in these lines, and our senses are consequently modified: on the other hand, the brain which in primitive man was probably less complicated than nowadays, has reached a much more complex stage of development to suit the altered conditions, when men fight in the struggle for existence with their heads instead of their limbs ; and this higher state of development in the brain must react on the senses in a manner immensely advantageous when considered in relation to the environment ; thus, though we can no longer hear sounds, which were clearly audible to our primitive ancestors, we are enabled to diagnose the sounds we do hear, and appreciate beauties in music to which the savage is still dead. Surely we owe too much to the great name of Charles Darwin — to the man who revolutionised modern science, and set things on a firm, because true, basis, to the man who devoted his whole life to the discovery of truth, in the face of enormous difficulties, who would cheer- fully have given up his pet theories one by one, could any one have convinced him that they were false ; surely, I say, we owe too much to him to accuse him of offering an insult to the human race because his use of the word rudimentary is not sufficiently nattering to our dignity or our pride. That our senses of hearing, etc., are comparatively rudimentary in some ways to what they once were is to me beyond doubt, nor can I doubt that it is best so, or that what we lose — if it can be called a loss — in one direction, we gain a hundredfold in another. But, since the desire to have the word altered seems to exist, and since the alternative offered— viz. vestiges — does not meet with approval, may I venture to suggest that the word "modified" be mentally substituted when the word "rudimentary" is found to be objectionable. I cannot however believe for one moment that primitive man was made up of "excrescences and deficiencies;" and to hint even that " abnormal " development of the organs of sight or anything else exists as a rule in nature is to me illogical, and more insulting to the dignity of the Creator than is Darwin's application of the word "rudimentary" to our organs to the dignity of the creature that was made in the image of God. — T. Alfred Dymes. Rudiments and Vestiges. — A writer in your last number seems to take somewhat vehement ex- ception to Mr. Darwin's term of "rudimentary," as applied to certain structures found in the human body, and deems it a slight upon mankind to speak of "vestiges." I confess I cannot see where the objection lies. In speaking of structures as "rudi- mentary," we use the term in comparison with structures of the same kind in a higher state of development. For example, the "down" covering a man's body is certainly in a more rudimentary con- dition as regards the hair on the lower animals, which is in a more advanced stage of development. Again, if we grant that man is descended from some lower form, the external ear and its muscles are but "vestiges" of the earlier form, which has gradually atrophied and become changed, as it was no longer necessary. We cannot say that they are in a higher stage of development, as the highest development of the sense of hearing is found in the lower animals. Then why is it not right to call them "vestiges," they are but the altered remains of our progenitors, and are undoubtedly in a " rudimentary " condition compared with the highest standard ? As for the os coccyx being a rudimentary tail, I imagine that most people sit down under the insult, with the greatest composure, and I do not see anything more com- forting to the mind, or more correct in science, in calling it an " excrescence." The teeth and jaws of the ape are surely superior to man in strength and biting power, and these are their only use, and I can see no reason why these structures in man should not be considered vestiges, and to be in a rudimentary condition as compared with the ape. Why should these structures be called abnormal in the ape ? They are perfectly natural and necessary. We might just as well say that man has an abnormal amount of brain, which would spoil the idea of harmony which exists to perfection, in every organism ? In every animal we look at, we find that all its organs are beautifully adapted to perform their various functions, and make up a harmonious whole. It is only the natural conceit of man that causes him to consider certain structures in the lower animals as unsightly. He compares them with his own, but looked at with regard to their anatomy, &c, they become beautiful. There is nothing in anything that Mr. Darwin has said, which must not strike us with increased awe and admiration for the marvellous changes and developments which Nature has brought about. — G. D. Trevor-Roper, Surgeon, R.N. Fox Eggars. — I have got some fox eggars, which I have had since the beginning of September. I have been feeding them on bramble ; now they have stopped eating it, and lie curled up in the bottom of the box. Could you tell me if they are hibernating, or if some disease has attacked them ? Nest of Australian Fly (p. 239). — From the particulars given by Mr. Browne's friend, it is impossible to identify this insect. I have little doubt, however, that it has four wings (flies have only two), and that it is one of the fossorial hymenoptera. Many of the English species, especially those of the genera Fompilus and Crabro, provision their cells with spiders. Some store up for their young other insects, such as flies, aphides, beetles, and lepidop- terous larvre. Towards the end of July last, I came across a large colony of Ccrceris arenaria, near Weybridge, and it was interesting to watch the females arriving on the wing at, and entering their burrows on the upright face of a sandbank, each carrying between her legs a beetle, always the same HARDWICKE'S SCIENCE-GOSSIP. 43 species, Stiorhynchus siilcatus, one of the weevils, and forthwith depositing it within as food for the larvae to be born from the eggs of the cerceris. On opening a burrow, moreover, there was a cluster of twenty or more beetles, neatly packed, each beetle being paralysed by the sting of the cerceris, and, while thus prevented from moving, still alive, so as to afford fresh food for the larvae, as and when required. Again, in August, I met with numbers of Odynerus sfinifies busy at a colony they had formed on the face of a cliff at Swanage, each female frequently arriving with a small green lepidopterous larva, with which it clambered up the curved mud funnel, forming the entrance to the cell, adding it to the heap of similar larvae which were found on opening a nest. Al- together the habits of this group of insects are very interesting, and are well worth investigation. — H. Ramsden. Ornithological Voracity. — On the 28th of November, Mr. Thomas Whitfield had the peculiar luck to find a dead kingfisher on the banks of the stream in Weasdale. Strange to say, it had appa- rently been choked in the action of swallowing a bull-head, the latter part of whose body was hanging out of its mandibles. — T/ios. Hexvetson, The Lane, Weasdale, Ravenstonedale, Westmoreland. Albino Rook. — This bird was shot at Newport, Monmouthshire, it being pure white or cream colour. — William Shakespeare, Naturalist, Cardiff. Bees and Lime-trees.— Your correspondent on this subject in last month's issue of Science-Gossip is quite correct in thinking that the juices contained in the flowers of the lime-tree {Tilia Europira) are possessed of poisonous properties, which prove fatal to bees that frequent this tree when in bloom. Hive- bees, humble-bees, and even wasps provide innumer- able victims to the intoxicating poison which they so eagerly imbibe from the flowers of the lime, and the numbers of dead insects which strew the ground underneath the trees testify to the fatal nature of the nectar which they imbibe. Some of them, after falling to the ground in an intoxicated manner, may escape the utmost consequences of their death-dealing repast, but to the great majority of them a short carouse amongst the blossoms proves fatal. I have not noticed that the thorax of the poisoned insect has been scooped out, but I have often found the head, thorax, and part of the body — one part of the body being gone, and the other part having the inside apparently scooped out. This I set down as being due to the dead insects having been blown about by the wind, the body, which soon gets to be stiff and dry, being easily broken at one of the joints. Then the spiders and earwigs take possession of the cavity. — J. Bowman, Havelock House, Sunderland. Names of Fishes. — Could any one tell me what is the correct name of a fish, of the carp species, having an arched back like a bream, but the true carp dorsal fin and plumpness of body ; the back a darkish colour, and the sides a beautiful gold, and a silvery gold lower, but when not catching the light, of a bronzy colour? Could this be the fish mentioned in Shirley Hibberd's " Fresh-Water Aquarium," as the Crucian or German Carp (Cy- prinus carrassius), of which he says, it "is easily distinguished from its compeers by its bream-shaped back, which rises from the nape into a high arch along the line of the dorsal fin. It is found in the Thames between Hammersmith and Windsor," etc. And also what is the name of another carp, back dark, slightly tinged with dark red, and two reddish marks on the head, and the sides of a very brilliant gold bronze, and preserving the true carp outline and fins ? Also of one exactly like the last, but without any red tinge ; and another the same as that but having the dorsal tin on the centre of the back, like a tench's ? — A. G. Whishaw. Convolvulus Hawk Moth.— On August 31st last, I had a very fine specimen of the convolvulus hawk moth brought to me alive ; the wings were slightly rubbed. It is the first living specimen I have met with, but some years ago a woman showed me a chrysalis, which, from the projecting proboscis, something like the handle of a pitcher, and its large size, I believe was the chrysalis of this moth. — C. F. George. Cuckoo. — In answer to Mr. Wallis's question in November " Gossip," whether I really saw the bird, I can assure him it was even as I stated in my previous note. I saw the bird, and saw the move- ment of the throat during the utterance of the sounds, and the bird flew away still crying cuckoo-koo. I have frequently heard the bird since in the same locality uttering the same three syllables. — F. J. George, Charley, Lane. Cuckoo's-Mate. — Mr. W. E. Windus says (page 259) of the wry-neck (Yunx Tonpiilla) : " It is, I should think, of insectivorous habits." I find that Gilbert White, of Selborne, says of it in his "Observations on Birds : " " These birds appear on the grass plots and.walks. They walk a little as well as hop, and thrust their bills into the turf, in quest, I conclude, of ants, which are their food. While they hold their bills in the grass, they draw out their prey with their tongues, which are so long as to be coiled round their heads." — Thomas Winder, C.E., Sheffield. Feeding Frogs and Newts. — In "Notes and Queries " for October, a correspondent asks for in- formation respecting the feeding of the above. During the summer months, I give my little batrachians a plentiful supply of small insects, cater- pillars, house and meat-flies and their larvre, and small garden worms. For winter's use, I always keep a number of the latter in earth in flower-pots or boxes, so as to be able to feed my pets when hungry, and when food outside is not easy to obtain. _ It is a common mistake to keep newts continually in water as if they were fish and not amphibians. I have a number of newts, salamanders, and green-tree frogs in a large fern-case, with a small earthenware pan for water, to be used as a bath. By paying attention to their habits, and giving them a constant supply of food, I have been able to keep some of my newts in captivity for four and five years. My warty newts are very partial to raw beef cut into small shreds, but the smaller species and the frogs will seldom touch it. The latter are especially fond of small earth-worms (and the warty newts also), and it is very amusing to watch the antics of froggie busily engaged in swallow- ing a worm, in which proceeding he is greatly assisted by his fore-feet, which are used to brush away the superfluous earth, and to stow the ends of the worm quickly and snugly into his mouth.— A. J. Jenkins, New Cross. Educational Collections of Insects.— It may interest Mr. Bath to know that, in conjunction with Professor Westwood, I have had the honour to fit up 44 HARDWICKE'S SCIENCE-GOSSIP. such a collection as he names (S.-G. p. 253) for the Agricultural Department at S. Kensington. I have also fitted up collections on somewhat different lines for the Royal Gardens, Kew ; Liverpool Free Museum, and other places, and am now appointed by the S. Kensington authorities to fit up collections for any institution receiving government support, that may require them. — S. L. Mosky, Beaumont Park Museum, Iluddersfield. Sphinx Convolvuli. — This fine species seems to have been not uncommon in the neighbourhood of Birmingham last season. I have heard of three captures, one in Moseley, and the others in adjoining parishes. — K. D., Co/ton. Temminck's Stint. — During the autumn migra- tion a specimen of this bird was shot on the edge of a large piece of water in this part of Worcestershire. — K. D., Co/ton. The Ivy. — It appears to me that Mr. Williams has wandered a little from the point in his reply (p. 257) to C. C.'s remarks (p. 236), the case of the flower-stem which he quotes not being quite a parallel one. The stem of the flower is the channel through which it receives its main nourishment, and is equivalent to the main stem of the ivy, whereas the rootlet of the ivy is evidently not the main channel of its nourishment, but only at best a minor one, if even that. It does not follow that C. C. is correct, however. Cut through the main ground- root of the ivy, and the plant dies, as he remarks ; but this does not at all prove that the rootlet conveys no nourishment or moisture whatever to the plant. I take it the chief function of the rootlet is similar to that filled by the tendril of the pea, viz. to cling. Most walls are more or less damp externally, and that being so, why should not the rootlet in course of time evolve some process by which it could absorb this ready-to-hand moisture, and so aid the main stem in its work of sustaining the plant? Ivied walls have had the reputation of being damp, and the question seems to be whether the damp attracts the ivy, or the ivy attracts the damp. It ought not to be difficult to ascertain whether ivied walls really are damp or not. — F. M. The Singing of the Kettle. — The explanation of this familiar phenomenon, given in Science- Gossip for December, pp. 275-6, by Mr. Williams, is the correct one. The air dissolved in water is expelled in boiling, and if the singing depended on the elimination of air, no recurrence of it would take place by replacing the kettle on the fire. Yet every boy who has experimented with a kettle knows how readily the kettle will sing by alternately heating and cooling the water. — D. S. Flies and Ants. — I shall feel much obliged if any of your readers can give me a clue as to what was going on in the incident detailed at foot hereof. I was staying at Sandovvn, I.W., last summer, and one Sunday afternoon (7th August), about four o'clock in the afternoon, I observed an enormous number of black ants running about all over a con- crete path, up some short iron railings, and over the bed and grass adjacent to their nest. Besides the ants were a great number of a peculiar-looking fly, which I do not remember having noticed before. They were about .', in. long, dark sepia bodies (almost black), with the segments distinctly marked, moniliform antennre, short plump abdomens, which did not extend to the end of the wings when the latter were folded on their backs. Their movements were slow and deliberate. The number of their wings was four, consisting of a thin transparent sub- stance like the house-flies'. Query name ? Besides those of the above-mentioned size, there were about an equal number of smaller ones, not much more than half the size of the others ; but I think of the same species. Both flies and ants were running about in a distracted sort of way, and to all ap- pearance having no object in their movements. The larger of the flies were collected at the tops of the railings, over whose rounded summits they moved in much the same manner as a bee over a ball-shaped flower. Neither flies nor ants attacked one another, but rather the reverse, for when they met both seemed to try and get out of the way of the other, and went off in different directions. — Amator Natures. Vanessa C- album. — During September last year, this butterfly was common along the west side of the Malvern Hills. I caught several specimens during the month, but only one in August, on the 9th, which seemed as if it might be a lingering specimen of a July brood. Is it certain whether C-album has two distinct broods or not ? I find in Newman's "British Butterflies": — "An idea seems prevalent that there are two broods in the year. ... I think this is a mistake ; I have been able to obtain no satisfactory evidence of any caterpillars prior to those so abundant in the autumn months about the season of hop-picking." Now the butterfly I caught on August 9th (and Newman admits he has seen it in June, July, and August), certainly cannot have been a hibernated specimen, or the imago of a cater- pillar feeding "about the season of hop-picking." C-atbum's favourite flower seems to be bramble ; indeed I tried a long while on the 20th of September after three or four which were settling on a clump of brambles. Every time I struck at one or other of them my net got caught and torn, while the butterfly took a few turns in the air and then re-settled. I noticed that when a cloud passed over the sun, they would fly into a high tree near, and close their wings till the cloud had passed. Another flower these butterflies seem attached to is Scabiosa suecisa ; in- deed these two were the only flowers I saw them on. Although usually a comparatively shy insect, I saw several flying about the high road on two warm sunshiny days, September 19th and 20th. Is it known whether the curious and beautiful variation of the underside is merely individual ? I caught several specimens with the dull brown underside, and several others of the variegated, green, and different shades of brown variety. I should be very interested to get information on these points. — A. G. T. Yew-Tree poisoning Cattle. — The question of cattle being poisoned by eating the leaves, etc., of the common yew-tree (Taxus baceata), was discussed at some length in Science-Gossip for the years 1879 and 1880. Many instances were brought forward in proof of the poisonous nature of the plant. Yet at the very close of the correspondence on the subject, a writer hailing from the co. Tyrone, asserted that cattle could feed with impunity on the yew, and cited a case he had met with. Now for the satisfac- tion of those who consider the yew to be poisonous eating for cattle, and for the conviction of those who do not, I ask room to record a case that occurred on the 1 6th of November, 18S7, in the demesne of the Earl of Caledon, co. Tyrone. A number of cattle were taken violently ill, and eight bullocks and one sheep died with every sign of having been poisoned. HARDWICKE'S SCIENCE-GOSSIP. 45 A veterinary surgeon, Mr. Moir, of the city of Armagh, was sent for, and he made a post-mortem examination of the dead beasts, and found in all their paunches a quantity of yew-leaves, and to them and nothing else could be attributed their death. The cases have been reported at full length in the Belfast newspapers of the 17th of November, 1887. — H. W. Lett, M.A. Cats and Violata. — In our garden, we had a good many roots of Viola scmperfloreiis which seemed to be eaten by snails and caterpillars. But one day, to our surprise, we found a cat contentedly munching the leaves. This happpened more than once afterwards. The cat never seemed to suffer in the least from the effects of its curious meal. Can any reader account for this extraordinary feast ? — A. Verinder. Popular Science. — A Suggestion. — One pro- minent feature in Science Gossip, rendering it a welcome visitor to the homes of many English naturalists, doubtless is that it is constantly endeavouring to foster a love of nature in those with whom it comes in contact, and most especi- ally in those just entering upon mature life. The facilities its pages offer for recording facts of interest ; the excellent medium, it is so well recognised as being, whereby specimens may be exchanged, or mutual sympathy and help secured, each combine to render it a great promoter of those pure pleasures the observation of nature so invariably gives to those who practise it. There are many who, with sympathies keen as our own to appreciate the beautiful in things around them, yet pass through life apparently unconscious of much in their sur- roundings which excites the admiration of, and affords pleasure to, their fellow-men. Let us take as an instance the case of young men engaged in business in our large towns. How many of them are there who know practically nothing of the wonderful facts revealed by the microscope ! A chance paper here or there, or an occasional peep through its secret-revealing tube, bounds their knowledge, and, alas ! also their interest in the great world of little things. For these persons of little opportunity let me bespeak the sympathy of "our readers," and ask each one having the oppor- tunity to seek to increase and extend the knowledge to others their training and experience has rendered so pleasurable to themselves. Particularly available is this suggestion to persons united with associations formed for the purpose of mutual culture and improvement ; such as are to be met with in most of our large towns and in not a few of our villages. An experiment to this end has recently been made by the writer of this article, with most encouraging results. Our course of proceeding was simplicity itself. We first secured the aid of a few friends by asking them to place their microscopes at our disposal for an evening. We (that is my friend Mr. Wooller and myself) then gave two short addresses, announcing as a principal feature that the objects chiefly referred to in our remarks would be exhibited for inspection, and further that we were willing to give all information in our power to reasonable querists. Cnoosing as my subject the past influences of minute organisms, such as foraminifers, diatoms, &c, in building up the hills and rocks around us ; and also referring to their unobtrusive but important functions still going forward, I emphasised my remarks by exhibiting a series of slides under the microscopes, illustrative of the subject. After a short interval for general conversation and refresh- ment, Mr. Wooller spoke upon the revelations of the microscope regarding our immediate sur- roundings, referring particularly to the light it has thrown upon the germ-origin of disease, and also upon the question of spontaneous generation. After which a number of living diatoms and other minute forms of vegetable and animal life were introduced for inspection. I have frequently given my services as an exhibitor of microscopic objects to the pro- moters of social evenings and similar gatherings, but nothing approaching the interest evidenced at the meeting referred to have I before witnessed. And this fact I attribute entirely to the circumstance that, by reason of our explanatory remarks, the friends present were able to understand somewhat the nature of the objects at which they were invited to gaze. Feeling there must be many readers of Science-Gossip acquainted with these societies and similar associations, I make bold to plead that an experiment, so satisfactory to its promoters, should be repeated by those located in other districts who possess kindred sympathies and like opportunities. The numerous queries, as to the cost and amplifying powers of the various microscopes employed, point hopefully forward to a time when some whose interest was thus cursorily aroused may adopt a more permanent pursuit after the knowledge of those beauties and marvels of nature so lavishly distributed around them. — T. Corlidge. Pond Dredging and Collecting. — Will some reader be good enough to give a few hints on collecting Infusoria, Rotifera, Polyzoa, &c, stating best description of net to use and how to use it ? The information would, no doubt, be interesting to others besides myself. — L. Yew-Trees, their Size and Age. — With refer- ence to your correspondent P. J.'s query, the late Mr. Edwin Lees, in his "Botany of Malvern" (p. 100), says : " The two finest yews in the Malvern country are in Cradley churchyard — the largest is 26 feet in circumference at a yard from the ground. These may be calculated at about 800 years old." Now taking tr as 3|, 26 feet circumference gives 8T3T feet diameter, and about 50 inches radius. And if the tree is 800 years old, it has added a ring of the breadth of T'6 of" an inch each year. Surely P. J. is wrong in calculating the age of the tree by the length of the diameter. — A. G. Tanslcy. Yew-Trees, their Size and Age.— In the in- teresting note by P. J., p. 21 of the current number of Science-Gossip, there appears to be an omission of one item in making the calculation. Instead of the whole diameter, should it not be the half of it, and hence the age reduced in the same proportion ? By the method adopted each annual ring is reckoned twice over, that is, on the opposite sides of the centre. In the case quoted, the circumference of 33 feet would give a diameter of about 11 feet, and a radius of 5.^ feet. Then, taking a line as the average thickness of a year's growth, we have 5^x12x12 = 792 years, which is probably nearer the truth. We have a few yew-trees in churchyards in South Beds, and hope to have opportunities to measure them, when the results will be forwarded. —J. Saunders, Lutou. Yellow (or Ray's) Wagtail. — The note under this heading, page 22, is rather vague. S. M. C. does not give the date when the wagtails were seen, nor does he say how near his garden is to the town of Weymouth. If they were observed later than September, it is not likely they were Ray's wagtail 46 HARDWICKE'S SCIENCE-GOSSIP. but more probably the Gray Wagtail [Jlf. loarula), which has some bright yellow about it, though it is unusual to see so many as ten together. There is nothing improbable in Ray's wagtail dropping into a garden near a town when on passage. In Sussex Ray's wagtail is seldom seen after the middle of September. — William Jeffcry. V. Atalanta in Dundee. — During the past season, insects have been in abundance in this district ; it has been one of the best, during the last four years to my knowledge. As regards V. ata/anta, I may say it has been scarce. I spent a good deal of time searching for the larvae, and got about two dozen ; three of them as late as the end of October, when the last of them emerged from pupae as late as December 8th. They have been very scarce here the last three years. During the autumn of 1884 they were in hundreds, scarcely a plot of nettles escaped them. — Peter Kirk. Ancient Yews. — Through the courtesy of the Rector, the Rev. H. Hawkins, I am enabled to give P. J., Emsworth, particulars of a yew-tree, growing in Crowhurst Churchyard, Battle, Sussex. It measures thirty-three feet in circumference, and is supposed to be about 800 years old. A seedling yew has rooted itself in a crevice of the church tower. It is now a small bush about 70 years old, and, apparently, neither increases nor diminishes in size. If P. J., Emsworth, will send me address, I shall be pleased to forward for his acceptance a photo of the tree. — W. E. Windus. A Note on Philodina citrina. — In Science- Gossip for March, 1887, appeared a short note of mine on a variety of this species, which I found in the summer of 1886, in a stream near Cheadle, Staffordshire. This variety is very abundant on the moss covering some stones over which the water falls. More recently — namely in the summer, autumn, and winter of 1887 — I have found a few other races which certainly approach the variety very closely, though, perhaps, none of them differs quite so remarkably from the recognised form of the species. The most numerous of these lately found colonies is in a very similar situation to that in which the variety flourishes, the main difference being that the waterfall in this case is at the foot of a large pond. There is a more luxuriant growth of moss here than in the stream. The particular form of the species which I found here differs from the variety described last year in its smaller size and in the greater conspicuousness of the eyes, which, however, are still very small. The brown colour also is less marked, though it seems almost constant in the larger specimens. This race, however, has that uniform slenderness which Mr. Gosse found to be characteristic of the variety. On the whole, it may be said to be considerably less abnormal than the latter, but at the same time to differ markedly from the type of the species which must be familiar to students of the class from Mr. Gosse's figure in Hudson and Gosse's " Rotifera " (plate ix. fig. 6). The "strongly social manners" which Mr. Gosse, in a letter to me, ascribed to my variety seem equally characteristic of this race. I have seen a piece of moss in the live-box completely fringed with the protruded heads and necks of these Philodinae. Up to the present time, unfortunately, I have not been able to keep many specimens from this locality alive for more than a day or two. A few specimens generally maintained a lethargic existence amid the corpses of their fellows. The race which I propose to mention next, lives in close proximity to what I call the variety; that is, the form briefly described in Science-Gossip for March last year. The variety itself flourishes in a small waterfall ; this other race I have found in water dipped from immediately above the fall. It departs less widely than the form last described from the ordinary type of the species, for it has not the brown colour, and the colour is in this form, as in the ordinary type, confined to the central parts of the animal. But this also has the slenderness of the variety, and there is no abrupt transition from the body to the foot. There is here a tinge of green in the yellow colouring of the trunk. All the specimens of this race that I have seen are very much smaller than the variety, which indeed is one of the largest of the Rotifera with which I am acquainted. I have found quite recently in a small spring, the sides of which are covered with moss, a number of examples of P. citrina scarcely distinguishable from the variety, except by the fact that the eyes are less inconspicuous. These organs have here the oblong shape characteristic of the species ; but they are placed very far back, almost behind the masiax, even when the animal is fully extended. They are exceedingly small. I have also met with a race, on moss growing near the outlet of a large pond, which is not easily distinguished from the variety, though the brown hue seems less decided ; but I have hardly seen this often enough to be able to say much about it. The foregoing remarks seem to show that this pretty and interesting species is very variable. Mr. Gosse has stated, in Hudson and Gosse's "Rotifera," that the colour varies; but it will be seen that the form of the animal and the distribution of the colour also vary considerably. My experience also goes to show that the species is much commoner than has been supposed ; but it may be that it is common only in certain districts. It would be interesting to know whether other observers have found P. citrina in abundance on moss, especially in waterfalls ; and, if so, whether they have found the species to depart in any marked degree under such circumstances from the normal type. I have found examples agreeing well with Mr. Gosse's descriptions and figures (in " Rotifera " and in "Tenby") in several places near Cheadle, but never in any great abundance. In conclusion, I should like to express my great obligations to Mr. Gosse, who has most kindly answered letters of mine from time to time, and identified several species for me. — J. W. Plagg, F.P.M.S. Rudiments and Vestiges.— I fear the authority quoted a little depreciates Doctor Darwin as an expounder of Divine Providence, and considers the p/iusis kcrata taurois somewhat unsound. It will, however, be palpable that the reasoning requires the "image of God" in" man should be mental, neither can the distinct theological proposition of a physical "ideal form" be established in regard to the most helpless of animals, without a consideration of his surroundings, where we see adaptation as a portion of the operation. The difficulty as regards the theistical aspect of this question is the danger of making over to society perhaps, what was intended for philosophy. Preoccupied with such ideas, I put my elbow through a well-ordered case of beetles in a continental museum. Madame hastened to the scene in consternation. I offered to pay the damage. Madame must ask Monsieur. Madame suggested a franc, the sworded concierge demanded three — three were paid. A little after, Madame and a friend were observed to issue from a crockery ware shop, each with a basket in hand containing about a franc's worth of household requisites. — A. If. Sivinton. HARDWICKE'S SCIENCE-GOSSIP. 47 The Flora of Newfoundland and Labrador. — I am engaged in investigating the subject of the flora of Newfoundland and Labrador, of which very little is known, especially here in the country itself. For our knowledge we are mainly indebted to those few naturalists who from time to time have visited Newfoundland. I am now compiling a complete list of our flora, as far as it is known, and this appears at intervals in our St. John's " Colonist." I am also preparing for that paper, and ultimately for separate publication, articles on our "Wild Fruits and Berries." I should feel much obliged for help in the matter, especially in following heads : — 1. In what books or magazines (English or Ame- rican) can I find information as to our flora ? 2. To what societies or institutions (Linnrean), and to what papers could I apply for help, and which will feel an interest in my work ? 3. What magazines and papers would afford me most help as to botanical matters ? 4. Where could I obtain good coloured engravings of wild flowers and fruits ? 5. What books are available on the subjects of wild fruits, especially of England and North Ame- rica? 6. What are the cheapest and best books (with coloured plates) on North American and British ferns, mosses, lichens and seaweeds? I send you some local papers containing some of my articles, and, if you care for a complete set, will gladly send them ; they may be worth a notice in your magazine. I shall be glad to send, by parcel post, roots of some of our Newfoundland ferns and flowers, which are unknown or rare in England, in return for useful books and articles on botany. — Arthur C. Waghornc. Prolific Pond. — Since the foregoing (Science- Gossip, No. 272, Aug. 1887, page 1S5) was written, I have been fortunate in finding the following, which being added to the previous list brings up the number of species to forty-four, and so making my pond equal to the best recorded instance — I. Dinocharis tctractis ; 2. Notommata aurita ; 3. Furcularia ensi- fcra ; 4. F. mrfandricus ; 5. RIonostyla bulla ; 6. Di- gkua graudis. Nos. 4 and 6 are Mr. Gosse's identification, from a tube I sent him. No. 4 I do not know, but presume it is one of the new species which has to appear in the "Journal of the Royal Microscopical Society." — J. E. L. NOTICES TO CORRESPONDENTS. To Correspondents and Exchangers. — As we now publish Science-Gossip earlier than formerly, we cannot un- dertake to insert in the following number any communications which reach us later than the 8th of the previous month. To Anonymous Querists. — We must adhere to our rule of not noticing queries which do not bear the writers' names. To Dealers and Others. — We are always glad to treat dealers in natural history objects on the same fair and general ground as amateurs, in so far as the "exchanges" offered are fair exchanges. But it is evident that, when their offers are simply disguised advertisements, for the purpose of evading the cost of advertising, an advantage is taken of ovx gratuitous insertion of " exchanges " which cannot be tolerated. We request that all exchanges may be signed with name (or initials) and full address at the end. R. P., jun. (Airdrie). — The flat zoophyte is Membranipora tnembranacea, the other Scrtularia jalcuta. The little round objects are the cases of a marine worm (Spirorbis). The objects from Macassar Straits are a species of the larger tropical foraminifera. C. C. Dallas. — Judging from your rough sketch and de- scription, we believe cup-shaped object attached to a twig is the empty pupa case of one of the saw-flies. J- H.— See Maund's " Botanic Garden." Capital illustra- tions of the tea-plant may be seen and studied at Kew, where all information might be obtained. Miss W. — There is no doubt your shell is a cowrie [Cyprea. caurica or C. lynx, but it is impossible to be certain from a verbal description only. A. R. T. Winchlev. — "Up the River from Westminster to Windsor" was published by Hardwicke and Bogue in 1876. Apply for information concerning it to Messrs. W. H. Allen and Co., Waterloo Place, London. C. D. — Your lichen is Cladonia cornucoj>ioides. Get the "Young Collector" series on "Lichens and Mosses," price is. (Swan Sonnenschein and Co.) ; afterwards Lindsay's " British Lichens," price 10s. 6d., coloured plates. F. Lannon. — Get Coleman's "Our Woodlands, Heaths and Hedges," illustrated, price 2s- 6d. Mount your sections of woods in Canada balsam. I. Bowman. — We shall be very pleased to receive your ornithological papers. T. B. G. — Your mineral is a crystal of selenite from the London clay. X. R. — You will find a full description of fossil encrinites (with illustrations) in Taylor's "Common British Fossils, and where to find them," price 7s. 6.1. (Chatto and Windus). C. T. H. — One good method of mounting the smaller fossils of the Bartar clay is on black paper within glass-topped boxes. EXCHANGES. Wanted, skins of British mammals, particulirly pole-cat, water-.'hrew, badger, otter, martins and chiroptera. Many valuable works on natural history offered in exchange. List on application. — W. Harcourt Bath, Ladywood, B.rmingham. Wanted, Star-fishes and sea-urchins ; must be in good condition. Books and specimens of natural history offered in exchange. — W. Harcourt Bath, Ladywood, Birmingham. Wanted, stalk-eyed Crustacea (British). Good return made. — W. Harcourt Bath, Ladywood, Birmingham. Wanted, small serviceable microscope ; will give in ex- change a solid silver verge hunter. — A. G. H., 10 St. John's Hill, New Wandsworth, S.W. Will give a small collection of mounted seaweeds, 2 vols. "Family Friend," several numbers of " Cassell's Popular Recreator," in cover with leather backs, few fossils, &c, for "Dana's Mineralogy," or Lyell's "Geology." — A. G. H., 10 St. John's Hill, S.W. Offered, British coleoptera, for insects of other orders to illustrate mimicry, or pairs in which the sexes show great difference of form or colour. — C. H. Goodman, 9 Dorlcote Road, Wandsworth Common. Wanted, copies of Schuckard's "British Bees," and of Newman's " Butterflies and Moths." — R. B. Postans, 14 Enys Road, Eastbourne. Should be obliged if conchologists would send L. peregra and vars. from any localities. Good exchange. — F. K. Fitz- gerald, Harrogate. Wanted, British and foreign clausilia. Good exchange.— Fitzgerald, Harrogate. Lyell's "Travels in North America," 2 vols., and " Second Visit to the States," 2 vols. What offers? — C. L. Lord, 34 Burlington Crescent, Goole. Wanted, some common frogs (preferably in their winter torpor). Good exchange in books, etc.— J. Eyre, 4 Render Street, New Cross Road, London, S.E. Wanted, in exchange for fossils, flint or bone implements, from any locality.— A. T. Tichborne, Lodge, Oakfield Park, Croydon. Wanted, Annals and Magazine of Natural History ; books on spiders, sponges, gorgonias, etc., or material. In exchange I will give other books, very superior microscopical slides, etc. —Rev. J. E. Vize, Forden Vicarage, Welshpool. Full-grown frog wanted. Will give micro-slide in exchange or pay postage.— J. M. Bain, n Bothwell Street, Glasgow. Lantern views only once used ; about 2 dozen fine Sco:ch views in exchange for apparatus or books. — J. M. Bain, 11 Bothwell Street, Glasgow. 43 HARD WICKE ' .S S CIE NCE- G 0 SSI P. Wanted, specimens of British bees; will give in exchange Lepidoplera, Co'eoptera or Diptera (the latter well set on cards, but unnamed). — A. E. J. Carter, 9 Argyle Crescent, Portobe'.lo, N.B. Wanted, birds' nests and eggs from all parts of the world ; British specimens offered in exchange. — J. T. T. Reed, Ryhope, Sunderland. Science-Gossip fur Sept. 1881 to March 18S2: ditto for June 1885 to Dec. 1885; "Out of Doors," by Rev. J. G. Wood ; " Manual of Injurious Insects," by Miss Ormerod ; and " Practical Biology," by Huxley, in exchange for Shuckard's "British Bees," Darwin's "Cross- and Self-fertilization of Plants," or specimens of Coleoptera and Hymenoptera. — A. E. J. Carter, 9 Argyle Crescent, Portobello, N.B. Wanted, Rocking, Roy's or other good microtomes ; will s;ive large quantity of first-class slides for them. — Fred. Lee Carter, Gosforth. Wanted, mounted or unmounted parasites ; will give others in exchange — 160 to select from. Send lists. — Fred. Lee Carter, 25 Lansdowne Terrace, Gosforth, Newcastle-on-Tyne. Wanted, a good microscope and accessories, in exchange for a collection, in album, of about 1200 foreign stamps in perfect condition; catalogue value, {,11. — P., 80 Leathwaite Road, Clapham Common, London, S.W. Good object for the polariscope — horn, bone, whalebone, chemical crystals, &c, also micro photographs ; good exchange in slides. Write first. — J. Boggush, Alton, Hants. Wanted, good dissecting microscope ; offered, well-mounted slides of rare objects, collection of echinoderms or other zoo- logical objects. — Charlotte Sinel, Peel Villas, Jerse}'. Micro Slii es. — A series of fern slides and others in ex- change for first-class micro and magic lantern slides. — Walter Henshall, The Hollies, Bredbury, near Stockport. For exchange: — Science Gossip for 1884, with eleven coloured plates ; what offers ? — John T. Foster, Little Driffield, East Yorkshire. Wanted, live or dead specimens of Vitrliia pelhtcida and varieties; exchange given in freshwater shells. — W. E. Co'.linge, Springfield Place, Leeds. In exchange for well-mounted micro slides, bound or un- bound vols, of Science-Gossip, a polished mahogany box to hold 104 microscopic slides. — Herbert Spencer, Masboro' House, Balham, S.W. A quantity of well-mounted and interesting slides and land and freshwater shells, Desiderata, Newman's " British Moths and Butterflies," Cooke's "Ponds and Ditches," and books on Coleoptera, pond life and micro natural history. — James C. Blackshaw, 4 Ranelagh Road, Wolverhampton. Wanted, foreign shells and corals, in exchange for fossils, books or cash. — J. W. E., 145 Milnrow Road, Rochdale. British and Australian marine zoophytes wanted. — J. W. E., 145 Milnrow Road, Rochdale. Science-Gossip complete for first twenty years, bound in double volumes, nearly new ; also large number of good micro- scopical slides, animal and vegetable —what offers? — Micro, 10 Belmont, Bath. Mouillefarine, 46 rue Sainte-Annes, Paris, wishes to do extensive changes with a botanist of the New World ; offers references. — Ch. Copineau, juge, Tribunal civil de Doullens (Somme). "Tomlinson's Cyclopaedia of useful Arts, &c. " (Virtue), 9 vols., cloth, numerous fine steel plates, &c. ; also "Know- ledge," Nos. 1-56, in thirteen monthly parts, as published, both clean and good, exchanged ; i-plate photo Iensjor magic lantern preferred. — Hughes, Assistant Overseer, Bangor, N. Wales. Wanted, named and localised English land, marine and freshwater shells, or foreign ditto ; exchange fossils, coins, &c. — F. Stanley, Margate. Wanted, named British or foreign birds' eggs, or preserved skins ; exchange coins, meda's, fossils or shells. — F. Stanley, Margate. Rotifcra. — Wanted, a few correspondents for occasional exchanges. — David Bryce, 37 Brooke Road, Stoke Newington Common, N. Wanted, continental, American and foreign plants and micro-fungi, in exchange for indigenous (British) species. Cur- rest ondence u'hh students of foreign micro-fungi invited. — Rev. Hilderic Friend, F.L.S., Carlisle. Lei idoptera. — Duplicates: Sambucata, Tiliaria, Comit .ta, Megacephala, Ruberata, Rhomboidaria, Phragmitidis, Iota, Umbratica, S. Ligustri (1). Desiderata: numerous. — George Balding, Ruby Street, WUbech. For exchange, Planorlis glabcr, etc., for other shells. — John Clegg, 5 Derby Street, Millwood, Todmorden. For exchange, Plan, dilatatus and glabcr exchanged for other land and freshwater shells. — S. Clough, 20 Abingdon Street, Blaclqool. Wanted, recent editions of "Carpenter on Microscope," Eeale's " How to Work with Microscope," and Lankester's "Half-hour with Microscope," will exchange numbers of Science-Gossip. — W. T. Porter, 19 Otley Road, Headingley, Leeds. Good carboniferous fossils offered for other fossils, micro- slides, or electrical apparatus. — J. A. Hargreaves, Charlestown, Saipley, Yorkshire. Morpho cypris, Morpho menelaus, Morpho e?ga, the most dazzlingly beautiful of exotic lepidoptera ; what offers? — Joseph Anderson, jun., Aire Villa, Chichester. "Knowledge," in parts, 4 vols.; what offers? — Joseph Anderson, jun., Aire Villa, Chichester. Offered, first-rate slides of marine alga;, illustrating struc- ture and reproductive organs ; many species. Wanted, Kiitz- ing's "Species Algarum," and other works on alga;. — T. H. Buffham, Comely Bank Road, Walthamstow. For exchange, Helix serieea, Helix hortensis, var. olivacea. W anted, Limnea glutinosa, Limned invohita, Helix lamcllat.i, Helix pomatia, all vars. of Helix aspersa, except minor; all vars. of Helix capcrata, Bulimus acutus and its vars., and vars. albina of Pupa wnbilicata and Pupa marginata, and many others. — A. Hartley, 15 Croft Street, Idle, near Bradford. What offers for the following ? — 6 vols, of Lardner's " Science and Art;" 2 vols. "Handbook of British Fungi," by M. C. Cojke, M.A. ; 2 vol-. "Food and its Adulteration,'' by Hassall; 1 vol. "Materia Medica;" "How to Work with the Micro- scope," by Beale ; "Mounting Microscopic Object-'," by Davis ; a microscope preferred. — J. H. Morgan, St. Arvans, Chepstow, Mun. Fossils from all formations desired in exchange for other fossils from li s, magnesian limestone, &c. — Juhn Hawell M.A., Ingleby-Greenhow Vicarage, Northallerton. Ammon.tes and belemnites desired in exchange for fossils, minerals, shells, &c. — John Hawell, M.A., Ingleby-Greenhow Vicarage, Northallerton. Berg-meal, or mountain-meal, from Norway, slides, and a small quantity of material, both prepared and unprepared, in exchange ; good diatoms preferred. Send lists. — Rev. A. C. Smith, 3 Park Crescent, Brighton. Offered, complete clutches, with full data, of dipper, mag- pie, long-eared owl, tawny owl, black grouse, re 1 grouse, snipe, curlew, kittiwake and others. Wanted, over a hundred species of British eggs, in clutches, many of them not un- common.— B. A., Clifton House, Uxbridge. A lot of land, freshwater, and marine shells to name ; would any of your readers name these for me (true name required), and ii\ return would send two of e:ich species, if possible, for their trouble ? — John Jos. Holstead, 19 Millholme Terrace, Upperby Road, Carlisle. Wanted, Isocardia cor and other British shells ; exchange Cardium aculeatum and a variety of other kinds of marine and freshwater shells. — Mrs. Heitland, The Priory, Shrewsbury. :| BOOKS, ETC., RECEIVED. " A Flora of Hertfordshire," by the late A. R. Pryor (London : Gurney & Jackson). " Mineralogy," by Frank Rutley, third ed. (London : Thos. Murby). — " Elementary Text-book of Physiography," by W. Mawer (London : J. Marshall & Co.). " Report of the U. S. Commission of Fish and Fisheries fur 1885" (Washington: Government Printing Offices). — "British Frogs and Toads," by Linnaeus Greening. — " Butanical Record Club, Rept. for 1884, 1885, 1886."— " Trans. Royal Sue. U. S. Wales." — " Journal of Conchology." — " Book Chat." — " Scrib- ner's Monthly." — "The Amateur Photographer." — "The Garner." — "The Naturalist." — "The Botanical Gazette." — "Journal of the New York Microscopical Society." — " Bal- gravia." — " The Gentleman's Magazine." — "American Monthly Aiicroscopical Journal." — "The Essex Naturalist." — " Tne Midland Naturalist." — " Feuilles des Jeunes Naturalistes." — "The American Naturalist." — "Journal of Microscopy and Nat. Sci " — "Scientific News." — "Wesley Naturalist.' — "Naturalists' Monthly." — "La Science Illustre'e. — "Junior Review, Science, Lit. & Art." Communications received up to the 13TH ult. from: A. G. T.— W. B. G.—W. R. W.— P. B— C. R.— I. S.— J. T. T. R— T. H.— J. G.— G. K. G.— F. H. A.— A. H.— T. H. B.— J. A., jun— J. A. H.— W. T. P.— J. C.-G. B.— J. 11.— J. H.— A. C. S.— Rev. H. F.— B. A. C.—J. J. H.— If. — S. C— H. B.— F. S.— D. B.— H. O. H.— W. W.— J. H. G. J. W. E.-G. E. E., jun. -J. E. B.— J. W.— B.— F. L. C— \V. H.— W. E. C.-R. T.— C. R.— W. J.— J. T. F.— P. K.— C. D.— F. L.— W. E. W.— C. L.— I. B.— R. F. G.—W. E. W. — C. L W.-M. A. B.— F. R. F.-Z. W.— A. G. H.— G. E. E., jun.— E. W.-N. L.-&C. RARDWICK&S SCIENCE-GOSSIP. 49 NOTES ON GEOGRAPHICAL DISTRIBUTION. By T. D. A. COCKERELL. [Continued from page 26.] S regards the avi- fauna of the Colo- rado region, the Mexican and Ame- rican element is much more in the ascendant, and up to the present I have only observed four which are spe- cifically identical with those in the British list, and of these Ageltzus fhoz- niceus and Ceryk alcyon, are only occasional and cer- tainly not native in Britain, while Pica rustica is repre- sented by the va- riety Hudsonica only, and Anas boscas alone is quite identical with a native British bird. At present I have only two Colorado Crustacea on record, and of these Gamm&rus robustus is allied to our English G. pulex. The Arachnida have not yet been worked out, but they have a decidedly European stamp, and most belong to English genera ; the same may be said of the Myriapoda, the genera Julus, Lithobius and Geophilus having abundant species closely allied to their British representatives. The Coleoptera, with certain conspicuous excep- tions, are very like the British species, such genera as Amara, Bembidium, Cicindela, Pterostichus, Coccinella, Aphodius, &c., being well represented, while a Pcederus, very like littoralis, is common in certain districts, and I have found European-looking species of Meloe and Quedius. Many of the Hymenoptera are peculiar, yet there No. 279. — March 1888. are species of Bombus, Vespa, Odynerus, Chrysis, &c, resembling British forms. The Neuroptera are to a great extent European in general character. The Lepidoptera are also many of them of Euro- pean type, an Alucita resembling polydactyla (hexa- dactyla) is frequent on windows, and many other European genera abound. Of the sixty Rhopalocera I have on record, as inhabiting Colorado, only two, Vanessa antiopa and Dana'is plexippus, have been taken in England, and we know the last to be a recent introduction, but forty-nine belong to British genera, and Picris oleracea represents P. napi, modified by changed conditions, as does Vanessa milbertii, V. urticce, and several others are closely allied to European species. The Diptera are similarly for the most part of British genera, Tabanus, Tipula, Lucilia, and Muxa being abundant, and among the Hemiptera we find representatives of such genera as Leptocoris, Lygams, Miris, Calocoris, Notonecta, Corixa, Cimex, Cicada (5 species) and Jassus. The only two leeches' I have note of belong to the genera Aulostomum and Clepsine ; earthworms (Lumbricus) are rare, I am told that a few exist in Wet Mountain Valley, but I have not been able to secure an example. The flowering plants of Colorado have been ably described by Dr. J. M. Coulter, and present many features of interest. In the RanunculaceEe all the genera are British, as well as the following species :—Myosurus minimus, Ranunculus flammu la (represented by var. reptans), R. sceleratus, and R. trichophyUus. The only species of Papaver is P. nudicaule. Among the Cruciferaj are Draba incana, var. confusa, Cardamine hirsuta, Erysimum cheiranthoides, Nasturtium palustre, N. officinale (but this is an introduction, it has been found near Denver, and I found it on Saguache Creek, above Rock Cliff), Camclina sativa, and Lepidium D 5o HARD WICKE ' S S CIE NCE- G O SSI P. sativum. The seven species of Viola include J'. faluslris and V. canina, var. sylvestris. Cerastium alpinum (var. behringianuni) and C. arvensc occur, as well as Arenaria verna. Hypericum, so prominent in England, is represented by only a single species, II. scouleri. Astragalus is a huge genus, with forty- six species, including alpinus and hypoglottis. Fra- garia vesca is abundant. Six species of Saxifraga, hirculus, caespitosa, cernua, rivularis, stellaris (var. comosa), and nivalis are also British (Saxifraga is an essentially boreal genus. Lieut. Greely found S. rivularis (var. hyperbored), S. cernua, S. oppositifolia, S. nivalis, and S. c<rspitosa in the Arctic region of Grinnel Land). The six species of Epilobium include angustifolium, alpinum, and palustre (var. lineare). F. angustifolium is excessively abundant ; on Sept. 5th, I passed through a burnt-up spruce-forest on Pottery Pass,* between Wheeler and Red Cliff, and the charred trunks no longer shading the ground, a dense growth of this species had sprung up, together with species of Aster, &c, completely covering the soil. Adoxa moschatdlina is found, and Linntza borcalis and Galium borcale (this last I found on the Grand Mesa, at an elevation of about S900 feet). Erigeron is a large genus, and includes E. acris. Senecio has 16 species, but none are British ; the genus is probably boreal, but the species are unstable, and soon vary under new conditions. Hieracium, a large English genus, has only three species and a variety in Colorado ; but H. umbellatum is given as "from Lake Superior to the Rocky Mountains." Taraxacum officinale has the varieties alpinum and scopulorum, and I found an ordinary-looking dande- lion by Swift Creek, Custer Co. The three species of Primula are farinosa, parryi, and angustifolia. Parryi I found abundant on the Sangre de Cristo Range. Gentiana is represented by ten species — as might be expected of such a typically Alpine genus. Polemonium has four species, including cseruleum. Myosotis sylvatica appears as the var. alpestris, a forget-me-not of the most vivid blue, which I found growing in little compact bunches on the top of the Sangre de Cristo Range on August 4th, right above timber line, with Tarnassius (near to Apollo) and an Alpine Colias to keep it company. Chenopodium hybridum, glaucum and rubrum are found — I picked the last near Surface Creek, Delta Co. Poly- gonum has several species, but the only two British ones, P. aviculare (Pikeview, El Paso Co., July 13th) and P. convolvulus (Salida, Chaffee Co., Oct. 19th), are probably not indigenous. Humulus lupulus is common. The only species of Orchid common to Britain are Corallorhiza innata and Spiran/lies roman- zoviana (this last an example of the migration of boreal species into Ireland). The Juncaceae include Luzula campestris and spicata, and Juncus Jiliformis, * Tliis pass has no name on the map ; we named it so, because we found some fragmen's of ancient pottery and a stone arrow-head there. triglumis, castaueus, and tenuis var. congestus. The three Naiadaceae are Zannichellia palustris, Pofamo- geton rufescens (a Middlesex and Surrey Fplant) and P. marinus var. occidentalis. The representatives of Scirpus are ccespitostts, lacustris var. occidentalis, and sylvaticus var. digynus. Carex has forty-nine species, mostly European, or allied thereto, and includes C. pyrcndica, rupestris, capillaris, ampultacca, vulgaris, atrata, alpina, muricata, fcctida, vuipinoidea, disfidia, echinata, &c. The Graminese are to some extent peculiar, but the list includes Atopecurus alpinus, Calamagrostis stricla, Festuca ovina, &c. The twenty- two Pteridophyta have the following common to Britain -.—Isoetes lacustris (var. paupercula), Lycopo- dium annotinum, Botrychium lunaria (and also the doubtfully British B. lanceotatum), Asplenium septen- trionale, Phegopteris dryopteris, Lastrcea filix-mas (var. incisa, Mett.) Equisetum pratense and E. variegatum. The fungi have not yet been worked out, but there is no doubt that most of the species are also European. I have myself found Agaricus (Psaliota) campestris in more than one locality. Cases of poisoning, sup- posed to be due to Ergot {Claviceps purpurea) are reported by Professor Wm, Trelease. Farther north, the evidences of the boreal fauna and flora become even more apparent. I was much interested in examining the collection of the Ento- mological Society of Ontario, Canada,* and noticed therein specimens of the following British species from the immediate ^neighbourhood of London, Ontario : — Syritta pipicns, Apis mellifica, Metrocampa margaritata, Ennomos alniaria, Euplexia lucipara, Noctua ptecta, AT. c-nigrum, Agrotis saucia, Chelonia caia (var.), Nomophila noctuella (this a migratory species), Galleria cereana, Eupithecia absynthiata, Vanessa antiopa, V. cardui (this species is said to have occurred in millions in some parts of Canada in 18S5), Danais plexippus, Ptinus fur, and Chrywmela [Gastrophysa) polygon!. It is very probable that some of these species were introduced by human agency, but some are doubtless boreal. One feature in the collection was the presence of no less than twelve species of Plusia, none of them British. In the extreme north, where all the species are boreal, the proportion of species common to Europe becomes overwhelming. Greely gives a list of species found on the expedition to Grinnel Land ; of the nine birds eight are British, and of the twenty-five flowering- plants, sixteen belong to British species. 1 1 is list of Cryptogamia also includes Equisetum variegatum, E. arvense, Barbula alpina and Cladonia rangiferina. So much for the boreal fauna and flora of Britain. I will not now deal with the Eastern and Western groups, nor the Asiatic distribution of certain species. As regards Africa, it may be said that the portion south of the Sahara has no relation to the British fauna, and, perhaps with a few exceptions, alt the * Exhibited at the Colonial Exhibition; South Kensington. HARDWICKE'S SCIENCE-GOSSIP. 5* British species found in Africa, south of the Sahara, are either migratory or were imported by human agency. Certain European Lepidoptera are conspicuous in all African collections, and these I regard as belong- ing to the migratory group *— such are Achcrontia airopos (from Natal to Gambia and Kilimanjaro), Sterrha sacraria (Kilimanjaro), Chcerocampa nerii (Natal and Gambia), and the following species in a collection from Gambia — Dciopeia pulchclla, Heliothis peltigera, Plusia ni, Chcerocampa celcrio (a species wandering even to New Caledonia), Sphinx convol- vuli, and Lyccena Bietica. T. D. A. COCKERELL. West Cliff, Custer Co., Colorado. A CHAPTER ON BENZOYLSULPHONICIO- NIDE, OR SACCHARINE. By Dr. Alfred Crespi. SUCH is the somewhat uncouth and unfamiliar name that will soon be known to every one. It is the scientific designation of that singular sweetening agent which, though known to scientific men for some little time, came prominently before the public in the presidential address of Sir Henry Roscoe, at Manchester, six months ago. Such a name ought to cover properties quite cut of the common run, and when we inform the reader that saccharine— the name it will popularly be known by —is 250, or, it may be, 300 times as sweetening as cane sugar, his curiosity will be aroused. Unfortunately, the medical and scientific papers often contain reports, framed in all fairness and goodwill, of marvellous discoveries in electricity, chemistry, agriculture, and medicine, that it is con- fidently promised will revolutionise modern life ; and while we remain on the qui vive, looking out for more information, and hoping soon to profit by the discovery proclaimed in such warm terms, we wait in vain, and the world goes on in its humdrum way much as usual, neither the better nor the worse for the march of scientific discovery. It is reassuring to be told that saccharine will not drive cane and beetroot sugar from the field, for those familiar objects of daily use there will still continue some demand; but it will be useful in culinary operations, and as medicine, and as a flavouring agent, and perhaps in other ways. Its sweetening properties are remarkable. One grain of the ammoniacal hypo- sulphite of silver will render 32,000 grains of water distinctly sweet ; but one grain of saccharine, according to Professor Stutzer, of Bonn, will sweeten 70,000 grains of water. * Vide "Entomologist's Monthly Magazine," March, 1885, p. 233. Saccharine is one of the many derivatives of coal- tar, and was very fairly described by Sir Henry Roscoe, in a lecture at the Royal Institution, as "the most remarkable of all the marvellous products of the coal-tar industry." Now when all is remembered that coal-tar has done for mankind in the shape of providing colours, essences, and flavours, in the past thirty years, this is strong praise. Saccharine is a white amorphous powder, and when examined under the microscope, is found to have a crystalline appearance. It melts, or fuses, rather, at a temperature of 4240 Fahr., and then undergoes partial decomposition, while it gives off a powerful and easily recognisable odour. Placed upon the tongue, in its pure state, it is rather disappointing, as its sweetness is less marked than one would expect. Two explanations offer themselves : in the first place, it is not, in its pure state (nor will even the saliva thoroughly dissolve it) highly soluble in water; and in the second, its strength is so great that it deadens, by its very intensity, the nerves of taste, much in the same way as when we enter a brilliantly-lighted room, on a dark night, we are dazzled from the pupil being widely dilated, or, better still, much as a beam of electric Heht falling from a short distance upon the retina causes confusion of vision and dizziness. Saccharine must, therefore, be regarded as an essence, as par excellence the concentration of sweet- ness, and to get its full power needs free and in- telligent dilution. Vanellin, another of the many wonderful products of coal-tar, which is rapidly dis- placing the older and better-known vegetable flavour vanilla, is also overpoweringly pungent, and far pleasanter in a less concentrated form. In cold water saccharine is hardly at all soluble, and although it is more soluble in warm water, it is not till it is mixed with boiling water that it becomes very soluble. The completeness of the solubility is greatly increased by neutralising the fluid in which it is placed, and this can be done most readily by adding carbonate of soda or carbonate of potash, two suffi- ciently familiar articles in most well-to-do households. Saccharine expels the carbonic acid present in the solution, and soda or potash salts of saccharine are formed that taste almost as sweet as pure saccharine itself. Probably for commercial and domestic pur- poses saccharine will soon come into common use in the form of an alkaline powder. Messrs. Burroughs, Wellcome & Co. sent us some tabloids containinjr half a grain of saccharine, and equivalent roughly to a large lump of loaf sugar. We find that it is better to put the tabloid in the cup, and then pour in hot tea, coffee, or cocoa, and after stirring a few time?, adding the milk or cream. The flavour is in no way peculiar, but scarcely as agreeable as cane sugar, though use would soon remove that little objection. Alcohol, that powerful solvent of many alkaloids 5' HA RD WICKE'S SCIENCE- G OSS IP. and strong chemical agents, takes up saccharine freely. One gallon of a 40 per cent, mixture of alcohol and water will hold 1391*6 grains ; a gallon of 80 per cent, alcohol takes up 2250" 5, while absolute alcohol — that is to say, alcohol perfectly free of any admixture of water — only takes up 2llS"9 grains. This great solubility of saccharine in alcohol will be of much service to manufacturers of pure British wines, liqueurs, cordials, and essences. In practice, it is found more convenient to dissolve the sweeten- ing agent in warm solutions of alcohol and water. Warm glycerine also dissolves it well, but the pre- sence of glycerine would unfit the solution for domestic purposes. Saccharine promises to have three great fields before it, if not more. Its culinary uses may not be very great — though opinions are divided on that point — except for the preparation of sweetmeats and con- fectionery ; and as it has already been found possible to manufacture pure and wholesome sweets flavoured with it, and not containing cane sugar, it can hardly fail to give a decided impetus to the sweetmeat trade. Unfortunately it must not be forgotten that sugar is a valuable and cheap food, agreeing well enough with most people, and the substitution of minute quantities of saccharine for common sugar will diminish the nutritive properties of the foods to "which it is added. Again, it can be used to cover the sickening taste of many strong drugs, at any rate, the medical papers promise, in their usual hopeful spirit, great things in that direction. Every practical physician soon learns, however, that tasteless and so-called palatable prepara- tions of strong modern medicines are often, after two or three doses, most repulsive to the patient, and it may be found that after the first wonder is over, people will prefer the drug in its ordinary form to taking it mixed with saccharine. Time will show ; and we cordially wish the enterprising chemists who have taken up this part of the work all the success their good intentions merit. Lastly, saccharine is not changed in its passage through the body, and does not ferment like cane- sagar. It is also said to have powerful antiseptic properties ; in many cases, therefore, in which the aged sufferer craves for sweets, but cannot, without pain indulge in that, to him, dangerous luxury — cane- sugar — he will now, we must hope, be able to fall back upon saccharine, which, again, in many familiar, but not the less loathsome and destructive diseases, is found to be an invaluable help to the skilful physician. We have, we think, said enough to show that, much though the world owes to chemistry and to coal-tar, it is not often that a discovery like that of saccharine gives promise of greater things to come in the days, not perhaps far distant, when the chemist will, in his laboratory, manufacture many of the commoner and more useful foods. ]Vinibor;u\ THE VINEGAR EEL {ANGUILLULA ACETI). OWING to the fact, that vinegar is now usually freed from its mucilaginous impurities (on which this creature feeds), the vinegar eel is not such a common object for the microscope as it used to be. The mature female anguillula (Fig. 21) is about 7JI w " }— Fig. 22. — Head of vinegar eel, female. (*«) mouth ; {p/i) pharynx ; [oc) oesophagus ; (g) gizzard ; {*) intestine. X 250. Fig. 21. — Mature female. (w) mouth ; [ph) pharynx ; («) posi- tion of nervous ganglion ; (g) gizzard ; (z) intestine ; (z') lower portion of intestine ; [a] rectum ; \r) anus; (s) style. one-tenth of an inch in length, the mature male, one-fifteenth. Both sexes seem to vary in size. The body is long and filiform, of nearly uniform thickness, but tapering gently towards the head and less gradually towards the tail, which ends in a long, fine spine. The transparent body permits a close examination of the internal structure. HAEBWICKE'S SCIENCE-GOSSIP. 53 The females are viviparous, and the young may be seen in a mature female inside the body. In r j Fig. 24.— Young anguillula escaping. v.cl/. a, Fig. 23. outward form the sexes are very similar, the only difference being that the tail of the male bears three small processes (Fig. 23, /;-). broad testis, bent upon itself at its upper portion ; it opens by a very short vas deferens by the anus (Fig. 23). Two conspicuous spicula, shaped like the letter S and contained in sacs, are situated at each side of the vas deferens and open into it ; they act as claspers during the sexual process. In the female the generative opening is situated a little behind the middle of the body. This opening leads into an oval chamber and into the broad pouch. The large uterus, or broad pouch, seems more a cavity hollowed out in the body than a chamber with definite walls ; it passes forwards and ends in a long protoplasmic cord or ovary (?) which bends and passes over the intestine. The uterus is perhaps continued posteriorly, for I have found young sometimes in that region of the body, when the female contained many embryos. Young vinegar eels may be observed in the broad pouch in various stages of development. The youngest embryos are situated at the extreme end of the uterus ; the older ones nearer the generative opening. Some of the youngest may be seen, invested in a delicate shell, undergoing segmentation. The older ones exhibit a slow rotatory movement, which I believe is due to their rapid growth in length. The oldest of all have evidently escaped from the shell and move about uneasily. When the vinegar eel has finished its early stages of development inside the mother it escapes by the generative opening, wriggling its way through the somewhat narrow passage (Fig. 24, u). Soon after its escape it becomes very lively. Fig. 25. — Reproductive organs of female. \t) portion containing small nuclei ; (1- The intestine is not represented. (p) generative organ ; (c) chamber ; (s) portion of ovary containing large nuclei ; young eels in various stages of development; (A) interior end; (P) posterior end. The alimentary canal is a straight tube, traversing the whole length of the body cavity. The small mouth which opens anteriorly is surrounded by a horny capsule (Fig. 21, m). The pharynx (ph) has muscular walls with transverse strice, it leads into a narrow oesophagus (a?). The gizzard is round and very thick walled ; the muscular strise radiate from the small central cavity. The rest of the digestive tube consists of a long hind-gut or intestine (/) occupying the greater portion of the body. The anterior portion of this organ is broad and much serrulated ; near the reproductive system it becomes narrower and passes to one side. A short rectum (if it can be so called) leads to the anus, which opens near the root of the tail. The reproductive organ of the male is a long, The long ovary contains numerous nuclei im- bedded in a protoplasmic matrix. These nuclei are more crowded within a short distance of its extremity, where they disappear. I was not able to observe the excretary system. I believe it consists of long unbranched canals parallel to the long axis of the body, and opening near the middle. I do not know whether it is possible to see the nervous system without previous preparation. I have drawn (Fig. 22) a small round body (not easily discernible) lying above the gizzard ; but I cannot say whether this is the nervous system or a gland. Owing to the presence of fat globules scattered all over the body, it is difficult to observe many details of structure. Bernard Thomas. 54 HARDWICKE'S SCIENCE-GOSSIP. POND DREDGING AND COLLECTING. REPLYING to this query in the February number, I have much pleasure in giving some hints on collecting Infusoria, Rotifera, and Polyzoa, the result of my experience in this interesting pursuit. The necessary apparatus are : a collecting stick, a flat bottle, a pocket magnifier, and a handbag with bottles. Of all the various collecting sticks I have seen, I like none so well as the pattern supplied by Baker's, of High Holborn ; it consists of a hollow walking- stick, with an inner rod which can be drawn out to increase its length, a small bottle, a hook, and a ring for the net, all of which can be screwed on to the stick. The net should be made of dense muslin, with meshes small enough to prevent Rotifera and Infusoria going through, and yet allowing the water to run out freely. It is of some importance to have exactly the right material ; as a guidance, I may mention that on holding my net to the window I can see the light through it, but no object with any degree of distinctness, nor can I read through it ; when taking a dip the water runs through in about 5 to 10 seconds. The net should not be too long, nor too short ; 5 in. is a proper length, by 6 in. across the ring ; at the end is tied a small rimmed tube bottle of thin, clear glass, 3 in. long by I in. in diameter ; a common bottle of thick glass would be of very little use, because minute objects cannot be seen through such a bottle. The flat bottle was first introduced by Mr. Hardy, with the object of placing it under the microscope to examine its contents. I seldom use it in that way, because it is too inconvenient ; the stages of micro- scopes are not large enough to hold it, and so it is mostly necessary to hold and move it with both hands, leaving none free to focus the microscope ; I prefer to remove the weeds to a smaller trough. For use in the field and collecting, however, it is a most excellent contrivance, and quite indispensable. Every one knows how impossible it is to see an object clearly in a round bottle with a lens, whilst the flat bottle allows this to be done with the greatest ease. To make these bottles, get a thick piece of india- rubber, quite fiat, about 6 to 6h in. long and 2J to 3 in. broad, and -j or f in. thick, then cut out an inner piece all round, except at the top, at \ in. from the edge, the result will be a |j -shaped piece of indiarubber, against each side of which cement, with Miller's cement, a piece of thin plate glass, and the llat bottle is complete. One or two more and smaller bottles can be made with the remaining piece of indiarubber. I strongly recommend the indiarubber to be if in. thick, so as to make a deep bottle, other- wise the weeds, such as Anacharis, when put in with much difficulty, are pressed against the glass, which seriously interferes with their examination. The pocket lens should not be bi-convex, as is usually the case, but plano-convex, and used with the plane side towards the object. Having described the apparatus, I will now briefly mention how to use them. For the purpose of collecting, the Infusoria and Rotifera may be divided into two groups : the free swimming and those that are attached to water plants. For collecting the group of free swimming forms there is no better device than the net ; pass it through the water once or twice, and then hold it up and let the water run out — the condensed animals will enter the bottle quite at the last, like a cloud ; it is there- fore wrong to take a second dip before all the water has run out of the net. The ordinary dipping bottle, without net, is also useful and sufficient when the animals are abundant, but the net is certainly the best way of condensing them. At the same time, it is a mistake to condense pond-life too much, as the animals soon exhaust the food supply and die. Having ascertained with the pocket lens that the dip contains something, the contents of the tube is poured into another bottle. Some collectors take with them a number of small bottles for this purpose, but I prefer to have two or three large ones, with only one or two small ones, to be able to isolate an object on the spot when required. The group of attached Infusoria and Rotifera are best found with the flat bottle described above. Drag up with the hook a quantity of weed, and, selecting clean branches, but not the newest growth, place one branch after another in the bottle, which can then be carefully scrutinised with the lens. The tubes of Melicerta and Polyzoa, groups of Vorticella, etc., can at once be seen with the naked eye when present, and the good branches can soon be picked out. At the same time it must not be forgotten that some minute and very transparent animals, such as the Floscules, can rarely be seen even with the lens, and only the microscope at home will reveal all the captures. Experience alone can teach which of the branches are most likely to be prolific. As a general rule old-looking, but still sound and green, branches are the best. The water milfoil (Myriophyllum) is the best of water-plants to examine and collect, on account of the ease with which it can subsequently be placed under the microscope, Anacharis being a very awkward plant in this respect. In placing a weed in the flat bottle never put in more than one branch at a time, otherwise the branches will only obscure each other, and render examination more difficult. For Polyzoa it is best to dredge up weeds from the middle of the pond or canal by means of a loaded hook and line. Having selected the most promising branches out of various ponds, I place them all in the large bottles with the water to be taken home. Care must be taken not to put too many weeds in the bottles ; in the first place, no one has time to examine so much HARDWICKE'S SCIENCE-GOSSIP. 55 material, and secondly, such crowded bottles very quickly go wrong. On arriving home, I turn out the contents of the bottles into three or four small window aquaria having flat and parallel sides. I would here strongly recom- mend the use of these window aquaria for keeping and examining pond-life ; they save a great deal of time and trouble, and I find them quite indispensable. Mr. Watson, glass cutter and aquarium maker, of 161, Great Portland Street, London, makes them ; 6 in. long by 5! in. high, and 8 in. by 6 in., are two convenient sizes. A number of objects escape notice in the ordinary round aquaria and bottles, but in these flat aquaria, which are not more than 1 or ij in. thick, every part can be seen and examined with the pocket-lens with great ease. On placing the aquarium in front of a window or lamp the free swimming forms will collect on the side nearest the light, and any one of them, even the minutest, can be picked up with a dipping- tube, provided with an indiarubber teat, acting as a syphon. I need hardly mention the necessity of examining the objects as soon as possible, and not later than the day after their having been collected, as many organisms soon die in captivity, presumably from want of proper food. The life of Rotifers can be prolonged a little by feeding them twice a day with a green soup, made by crushing some Anacharis, or any other water weed, in a little water in a mortar. That they really eat this, can be seen under the microscope. After several days' captivity Rotifers look very white and hungry, biting at each other and trying to swallow each other's spines ; but when a few drops of the soup are added to the trough, their stomachs very soon assume a more comfortable green appearance, becoming filled with little balls of chlorophyll. In conclusion I would recommend microscopists to examine ponds and collect in winter as well as at the other seasons, for in my experience Rotifera and Infusoria are then, even under the ice, as abundant, if not more so, than in the summer months. I trust these few remarks will be found useful to the younger collectors ; I have found the methods described most efficient and time-saving, which is an important consideration to most of us who pursue this study as a recreation. C. ROUSSELET. RUDIMENTS.— A REPLY. IN discussing the advisability of retaining Mr. Darwin's use of the word "rudiment," it will perhaps be well to consider first the right application of the term. Either the organ so designated must be in an early stage of a future development, or in an inferior condition, compared with a higher standard. Your correspondent Mr. Trevor-Roper attributes the latter sense to Mr. Darwin. Now, as the term "rudimentary" can only be used in relation to a recognised standard of per- fection, we are forced into the strange position of seeking for the perfection of our so-called rudi- mentary organs in the lower animals. To those who have grasped the theory of develop- ment, this cannot but appear an anomalous pro- ceeding. The brain of man, so undeniable in its superiority, has perhaps alone escaped the stigma of being "greatly reduced from a perfect state," and to it is attributed solely the dominating position in which man now finds himself. We have been told that our sight, hearing, smell, etc., are in a lower state of development than that of our earlier progenitors severally, and we have ac- cepted the statement with unquestioning reverence. So with teeth, lungs, the down on the body, and indeed, almost every part of the human structure. But we must ask if these assertions will bear examination, and whether our senses are inherited " in an enfeebled and rudimentary condition," as Mr. Darwin states of the sense of smell. I am inclined to doubt it, and before deciding hastily which is rudi- mentary and which is perfect, to weigh quality with quantity, to consider the economy of material, to find, if possible, the most comprehensive capacity in the least space. And where is it to be found ? Not in the compound eye of the dragon-fly, though it sees " equally well in all directions — before, behind, or laterally," nor yet in the far-sighted eyes of certain birds, that may excel in distance of vision, but in the organ of sight, which, one of our greatest anatomists tells us, " arrives" in man " at its highest perfection." Put the dragon-fly or the bird into a gallery of pictures, and it is clear that delicacy of colouring and disposition of light and shade are lost upon them. Even the beauty of a landscape, or a fine sunset, excites no pleasurable recognition of harmonious tints. Certainly, according to Mr. Darwin, wonderful changes have been wrought by the preference of the female Polyplectron for the ball and socket ocelli in the plumage of the male bird, but this is a suppo- sition to be weighed ; and even allowing this, no one, I suppose, would venture to compare, for delicacy of perception, the bird's eye with man's. And again, with regard to the sense of smell. The bloodhound can track out and discover a runaway slave by the mere smelling of a garment, but has no perception of, or delight in, the varied scents of flowers, though carrion attracts him. The sense of smell is keen, but not refined. It is quantity versus quality. How, under these circumstances, can the sense of smell be said to be inherited by us "in an enfeebled and rudimentary condition " ? 56 HA RD WICKE'S SCIENCE- G OS SI P. A dog will hear distant sounds, and prick up his ears at the rolling of carriage-wheels, unperceived by us, but musical harmonies are wasted on him, or even disliked, and a new chord struck, or the song of a bird, is apparently unrecognised. Again it is quantity versus quality. And if we are driven to defend the down on the human body, and even the os coccyx, we shall find the same argument to hold good. As a matter of fact, the fur of lower animals corresponds strangely to the rudimentary condition of our own liner covering. In a very early stage of man's formation, " the whole surface " of the body is "thickly clothed" with " wool- like hair," which Mr. Darwin himself recognises as "probably representing the first permanent coat of hair in those mammals which are born hairy." What authority, then, has your correspondent for stating that the "down covering a man's body is certainly in a more rudimentary condition as regards the hair on lower animals " ? Precisely the same may be said with regard to the os coccyx, which is known to project in an early stage. Again, the tail is the rudimentary condition of the more perfect shortened formation, and corresponds to the appendage in lower animals. While we are taught so carefully to trace in man's own individual development the picture of the great scheme of evolution — from the lowest of vertebrata to man, the highest — it is curious that this simple conclusion should have been overlooked. Are we still to term organs rudimentary, though we know that to increase them to dimensions of the lower animals would be to return to our own embryological condition, from which they had scarcely emerged? The brain of an adult baboon, Mr. Darwin tells us, corresponds in development to the human brain in its early rudimentary condition. With these facts before us, we may surely infer that the ape represents to us a creature fashioned after the likeness of our own rudimentary state, and the same could be said with reference to other low forms. Their structures are found to correspond to more or less rudimentary stages in man's individual early existence. If this be indisputable, the word "rudi- mentary " when applied to any part of a fully- developed human organism, is incorrect, and even where traces of a lower condition may be found, they should be regarded merely as an arrest of proper development from its own rudimentaiy con- dition. A curious question arises from Mr. Darwin's theory of the process through which organs have passed in becoming rudimentary. He says, "Rudi- mentary organs have been slowly formed through continued disuse, acting by inheritance at a corre- sponding age, aided by the principle of the economy of growth, all under the control of Natural Selec- tion." He explains the modification of an organ to a rudimentary state, through Natural Selection, etc., by the same slow processes that were required for its first development. But the question is, Where are we to look for the stages of its first progress to development ? If the fur of an ape were down developed to perfection, what is the history of its evolution, and on what ancient animal did rudimentary down first appear ? The answer is as startling as apparent. Supposing the simple brain of a savage, through use, inheritance, and Natural Selection, gradually evolves into the fully-developed brain of a civilised being, and then, in course of generations, through disuse, acting by inheritance, gradually loses its powers, the civilised man reverts to the savage. Thus, if the down of the ape is found on man in its undeveloped vestigial condition, we must argue that man was originally the progenitor of the ape, and his down the rudiment of the futuie fur. I cannot close this article without explaining that arguing on evolution ground only should I use such terms as "excrescences" and " deficiencies " with regard to organs in the lower animals, and I am prepared to defend the position, but my paper has already exceeded in length. To the non-evolutionist every group is perfect in its kind, and for its environ- ment. N. F. L. NOTES ON FOSSIL CONCHOLOGY. THE subject of these notes, is, I may say, a vast and almost an inexhaustible one, and it is very difficult to know where to begin ; therefore, I propose to deal, in the first place, with the genus Planorbis. The Planorbes are freshwater molluscs, and abound principally in still water, although, occasionally found in streams. The animal is elongated, slender, and rolled up ; the head is furnished with two long contractile tentacles, at the internal bases of which eyes are placed ; the orifices are on the left side ; the organs of generation distinct. General character. — Shell discoidal ; spire de- pressed ; volutions apparent above and below ; aper- ture lunate, crescent-shaped or sub-quadrate, impinged upon by preceding volution ; outer lip generally thin, sharp-edged, columellar lip spreading over the body whorls. No operculum. All fossil remains of this genus are found in fresh water, or transition formations. Pl.ANORBis, Geoffroy. Planorbis obtusus, Sowerby. (Fig. 26, 1, a, b.) — This very pretty shell has a smooth, shining, nearly polished surface ; it is depressed, nearly flat on the upperside, and slightly concave beneath. Thevolutions are four or five in number, separated by a deep suture, slightly convex on both sides, but rather more com- pressed on the under side than the upper, obtusely rounded at the periphery, and each nearly half- HARDWICKE'S SCIENCE-GOSSIP. 57 •concealed by the succeeding volution. The aperture is very oblique and bluntly heart-shaped. In the general form and rounded whorls, this species re- sembles P. spamacensis, but the whorls are not so numerous, and the aperture is more oblique. The lenticular form and angulated margin of P. lens will prevent its being confounded with that species. Planorbis obtusus is found in the upper eocene forma- tion, at Sconce and Headon Hill, Isle of Wight, and at Hordwell, Hants. Planorbis euomphalus, Sowerby. (Fig. 26, 2, a. b.) — This well-known species, which appears to be con- but as they approach maturity it becomes more and more obtuse, and frequently disappears ; the whorls then assume a transversely oval form, approaching nearly to that presented by P. rotunda/us. On the under surface, the inner margin of the whorls is bent rather suddenly towards the preceding whorl, and presents, in consequence, an obtuse angle, which runs round and defines the umbilicus. Transverse lines of growth are very conspicuous ; and frequently the surface of the shell also presents more or less numerous concentric raised lines, some of which are larger and more prominent than the rest. The aper- Fig. 26.-Fossil fresh-water shells. 1. (a and b) Planorbis obtusus; 2. (2) P. platystoma; 3. («) side view of adult shell ; (b) view of upper disc of P. euomphalus; 4. P. discus; 5. P. lens; 6. P. elegaus. fined to the] fresh-water formations, is equally dis- tinguished from the other Planorbes. It is a large discoidal shell, nearly Hat on the upper face, and presenting a wide and "deep umbilical cavity beneath ; the six or seven volutions of which the shell is formed are fiat or nearly so above, concave below, and each but slightly embracing the preceding volution ; the apex is concealed by the volution of the whorls. A clearly defined and rather acute angle, almost forming a keel, runs round the periphery of.the shell, and separates the upper from the under disc. This angle is always very conspicuous in the young shells, ture is subtrigonal, slightly impinged upon by the preceding volution, and very oblique. This species is found in the fresh-water limestone of the Upper Eocene formation, at Headon Hill, Isle of Wight. Planorbis rotundatus, Braid.— A rather large shell, formed of six or seven nearly round volutions, separated by a deep suture, and each slightly im- pinged upon by the preceding one ; the volutions are flatly convex on the upper side, convex beneath, and (like those of P. euomphalus) present an angle running round the inner margin near the umbilicus, which as the shell matures becomes almost obsolete. S3 HARDWICKE'S SCIENCE-GOSSIP. The upper face is nearly flat, while the under side presents a moderately deep and wide concavity. The aperture is transversely oval, and but slightly oblique. The strice of growth are very conspicuous ; and occasionally, although very rarely, the shells present fine concentric lines, similar to those which char- acterise P. euomphalus. In this species, however, the lines are finer and more crowded, and seldom extend beyond the first three or four volutions. The fossil remains of this species abound in the Upper Eocene beds at Sconce and Headon Hill, also at Hordwell, Hants. Planorbis discus, Edwards. (Fig. 26, 4, a. b.) — This well-marked species appears to be peculiar to the fresh-water formation at Sconce, Isle of Wight. It is a much compressed discoidal shell, nearly flat on the upper side and deeply hollowed out below. The five or six whorls of which it is formed enlarge rapidly, and each is slightly embraced by the suc- ceeding one ; they are much flattened above, slightly convex below, and obtusely rounded at the outer edge. In the young shell, the inner margin is bent rather abruptly towards the preceding whorl, and presents an obtuse angle which defines the umbilicus, similar to that presented by P. euomphahis and P. rotiuidatus. As the shell becomes matured, the under side assumes an almost regularly convex form, and the angle becomes obsolete. The aperture is oblique, and of an elongated heart-shape. Casts of this shell occur in great abundance in the fresh-water beds of the Upper Eocene formation at Sconce, Isle of Wight. Planorbis digyratns, Edwards. — The present, like the preceding species, is apparently confined to the fresh-water formation of Sconce, but is not so plenti- ful as P. discus. It is a moderate-sized shell, formed of four rapidly-increasing whorls, somewhat convex above, and rather acutely angulated round the inner margins on the under side, just above the umbilicus. The periphery, near the upper surface, presents an obtuse angle, from which the whorls shape rather abruptly towards the umbilicus, assum- ing in consequence a subtrigonal form. The aperture is slightly oblique, and bluntly obcordate in conse- quence of its being impinged upon by the preceding whorl. The umbilical cavity is deep, but not very wide. This species is, in the fossil state, ordinarily found as casts only, in the Upper Eocene beds of Sconce, Isle of Wight. Planorbis platy stoma, Wood. (Fig. 26, b, a. b.)— A small smooth shell, formed of three rapidly enlarging whorls, each embracing about one-half of the pre- ceding one ; the whorls are rounded, equally convex above and below, but slightly compressed on the upper side. The apex is wholly concealed by the involutions of the whorls. The aperture is wide, oblique, and bluntly heart-shaped ; the upper side is slightly concave, and the under presents a wide and somewhat deep umbilicus. Planorbis platystoma is found rather abundantly in the Upper Eocene beds at Sconce, Headon Hill, and at Hordwell, Hants. Planorbis lens, Brongniart. (Fig. 26, 5, a, b.) — This species is a small lenticular shell, slightly concave on each side, but more so on the upper ; the whorls are four in number, each embracing nearly one-half of the preceding one ; they are also slightly convex on both sides, but more so above than beneath, and angulated round the periphery, a little below the middle of the whorl. The aperture is heart-shaped, but not very oblique. The fossil remains of this species are found at Headon Hill, Isle of Wight, and Hordwell, Hants, in the Upper Eocene forma- tion. Planorbis tropis, Edward. — A minute shell, com- pressed and polished, and slightly sunk round the apex, and widely but not deeply umbilicated ; the four or five volutions, of which it is composed, are convex above and flat beneath, and compressed near the outer margin so as to present a prominent keel, which runs round the periphery a little below the middle of the whorl. The whorls embrace one another about one-half of the preceding one; the aperture is very oblique, and of a longish heart-shape. This species seems to be peculiar to the Eocene beds at Hordwell, Hampshire. Planorbis hemistoma, Sowerby. — P. kemistoma is a minute, smooth, depressed shell, concave on the upper side, almost flat beneath and compressed, almost angulated at the periphery, above the middle of the shell. The whorls do not exactly embrace one another, although the upper surface is partly concealed by the succeeding whorl ; the inner margin is bent abruptly towards the apex, and presents a conspicuous angle, which runs round the cavity. The aperture is oblique and subtrigonal, having the lower margin rounded. This species somewhat resembles P. clegans, but is smaller and more compressed. Fossils of this species are found in the Eocene formation at Hordwell, Hants ; Plumstead, Sund- ridge, and Rotherhithe. Planorbis clegans, Edwards. (Fig. 26, 6, a, b.) — This little planorbis is found in great abundance at Headon Hill, Isle of Wight. It is a small polished shell, deeply but not widely hollowed out on the upper disc, and slightly concave, almost flat beneath. It is composed of four or five volutions rounded on the periphery, marked by conspicuous lines of growth nearly perpendicular to the axis, very convex, and presenting a sharpish angle running round the inner margin on the upper surface, and but slightly convex beneath ; each volution embraces a third of the preceding one. The aperture is heart-shaped, and slightly oblique. This species is found in the Eocene beds at Headon Hill, Isle of Wight, and at Hord- well, Hants. Planorbis biangulatus, Edwards. — A depressed, small shell, slightly and nearly equally hollowed out BARBWICKE'S SCIENCE-GOSSIP. 59 on both sides, but rather more so above than beneath. It is formed of four or five volutions, convex on the upper side, and obtusely angulated round the cavity, in consequence of the somewhat abrupt inflexion of the inner margin towards the preceding volution. The periphery presents two angles, one rather obscure near the middle, the other more prominent, runs round the margin of the lower disc. The aperture is slightly oblique, and of a short heart- shape, but irregular in its form, owing to the greater convexity and the angulated inner margin of the upper surface of the whorl. Planorbis biangulatus is found in a fossil state, in the Eocene beds at Hord- svell, Hants. Planorbis Sowerbyi, Bronn. — This is a small depressed shell, slightly and nearly equally hollowed out on both sides ; but the umbilical cavity is deeper of the two. The volutions are three or four in number, enlarging rapidly, convex above and flat beneath, and having a sharpish keel on the periphery. The whorls are much concealed, each embracing about half of the preceding one, and the aperture is very oblique, and of an elongated heart-shape. Found in the Upper Eocene beds at Sconce, Isle of Wight. This species is believed to be very rare. Geo. E. East, jun. NOTES ON THE EIGHTH EDITION OF THE LONDON CATALOGUE OF BRITISH PLANTS. By Arthur Bennett. THESE notes are put together for the purpose of aiding those botanists who have felt that the changes introduced into the 8th ed. of the " London Catalogue of British Plants " need some explanation more than could be given in that list. I propose to take the 7th and Sth editions and go through them seriatim, noting the changes in name, and here and there introducing such notes as seem needful. I have awaited the completion of Mr. B. D. Jackson's " Observations on the Nomenclature of the Sth ed. of the London Catalogue," concluded in the November number of the "Journal of Botany"; this will ex- plain the somewhat late appearance of these notes. Thalictrum majus a is sunk under minus c. flexuo- sum in Sth ed. b. Kochii becomes a var. under saxatile, but it is almost certain we have not the true Kochii of Fries. What the T. saxatile of Cambridge- shire is, I cannot yet ascertain ; I have grown it for three years ; dried a series, and twice sent it to Con- tinental authorities : in both cases they will not give it a name. Probably the No. 4 and var. b are really T. Jacquinianum. The Batrachian Ranunculi are still far from satis- factory, and yet need continuous study. No. 18, d. Penicillatus, Hiern, should be taken out ; it is really only pseudo-Jiuitaus, with floating leaves. I consider that \dc should be taken out, as I do not believe the Scotch plant is the confervoides of Fries, but would rather place it under 15. 32, Ranunculus sardous, Crantz (not with a capital S), is J?, hirsutus, Curtis, and an earlier name. 35, R. jlabdlatus var. represents 32, R. clncro- pltyllus, of the 7th ; Nyman saying that our Jersey plant is not the plant of Linnseus. The var. should properly read " Europreus,'' though Nyman prints it as the Sth. 50. At the time the Catalogue was printed, it was uncertain whether our var. intermedium was the true plant of Ledebour ; since then, Dr. Caspary has pronounced plants, from several stations in Scotland I sent him, to be the true plant; so " Led." should be added, and "auct. angl." taken out. 59, Glaucium Jlavum, Crantz, takes the place of G. luteum, Scop. 61, Rcemeria hybrida, DC, was accidentally omitted from the 7th ed. It is the rare cornfield plant occur- ring near Swaffham, in Cambridgeshire. 62 £ should have the authority " Mill," instead of "DC." 76 c occurs but rarely, but is British. S5 bis will be Arabis alpina, L., discovered in Scot- land last year (1SS7). SS, Arabis sagittata, is A. hirsuta, Br., of the 7th ed. ; it has a var. b added, found in Ireland and Sussex. 96, Cardamine bulbifera, is Dentaria bulbifera, of the 7th ed.,but the authority should be " R. Brown," not " Syme." 105 should have the authority DC, not " Reich." 109 b. Hortii, Syme, is a var. found by the Rev. — ■ Hort ; in some parts it is the commoner form. 112, Thaliana should be Thalianum, Gay. 120 should bepe/folialum, Crantz. 135 b is a form often mistaken for D. tenuifolia. 143, Lepidium Smithii, will become L. hctcrostylum, Benth., and b. canescens, Gren. et Godr. 153/; is a form gathered in Shetland and Fife, probably elsewhere. 161 is H. canum, Dunal, of the 7th ed. 162 is H. vulgare, Gsertn., of the 7th ed. 165 b should have " auct." instead of " Besser," as the authority. 172 is V. stagnina, Kitabel, of the 7th ed. 179 is Poly gala depressa of the 7th ed. b. ciliata is a form gathered on the Gogmagog Hills, in Cambridge- shire. I Si, alter the authority to " Linn." 191 b is a form found in Lancashire and elsewhere. 192 is Silene iujlata, Sm., of the 7th ed. 196, the census of counties should be " 5S," and added to " a. anglica." 209, authority should be "Scop." 211 is Mcenchia of the 7th ed. 217 c should be taken out and added o 21S, as var. b. Edmonstoni, Beeby. 6o HARDW1 CKE 'S SCIENCE-GO SS/P. Cerastium arcticum, Lange, is certain for Snowdon ! Shetland ! Aberdeen ! 226 should have '"' Retz " added as the authority, not " Ehrh." 230 is Alsine rubella of the 7th ed. 231 is A. uliginosa of the 7th ed. 237 is Honkenya peploides of the 7th ed. 238 is Cheleria sedoidcs of the 7th ed. 243 is Sagina saxatilis of the 7th ed. " Lepigonum" is used instead of " Spergularia " of the 7th ed., the terminations of the specific names being altered. 251 b is a rare var. found near Plymouth. 255, the var. should stand a. repens, Pers. b. erectus, Pers. 264 is Hypericum dnbium of the 7th ed. 265 is H. tetrapterum of the 7th ed. 267 b is a var. found in the Channel Isles by Dr. Boswell. 276 is a species found in the Scilly Isles of late years. 281 should be M. pusilla, With., not borcalis, Wallr. 282, alter authority to " Hudson." 286, alter authority to " Roth." 290/', alter authority to " Schiibl." 292, alter to G. versicolor, L. 299, alter authority to " Linn." 312, alter to biflora, Walt. The census "99 "should be transferred from 327 to 32S/;. 335 c, alter authority to " Desv." 336 should be M. arabica, All. Melilotus is a troublesome genus, " with name alterations." 338 should be M. officinalis, Lam., 7th ed., No. 31S. 340, arvensis, Wallr., 7th ed., No. 320. 341, indica, All. ; 7th ed., M. parvijiora. 343 b is a var. for Scotland and Norfolk ! 345 should be ochroleucum, Huds. 346 should be squamosum, Linn. 363 is T. minus, Relh., of the 7th eel. 368 is L. major of the 7th ed. 372, specific name with a small " h." 380 should be O. viciafolia, Scop. 392, alter authority to " Linn." 405 should be L. montanus, Bernh. 407 should be P. spinosa, Linn. 408, alter authority to " Huds." The census " 112 " to " 413 " is an error. 4S6 is P. minor, Gilib. 487 is perhaps P. rubens, Vill. ? 48S should be P. silvestris, Necker. 495 should be P. palnstris, Scop. 497, alter authority to "Scop." 498 £ is hybrida, Willd. 500 should be A. argentea, Don. 504 should be P. polygamum, Waldstein and Kitabel. The roses need little explanation, but 510^ ought to be placed under 508 as var. d. 513, agrestis, Savi, is practically 467 of the 7th ed. 416 to 476, Rnbi, I make no comments on these difficult plants, feeling assured that the arrangement and nomenclature is only in a transition state. 528 represents 479 a and b of the 7th ed. 533 is 472, 7th ed. 534(5 and c are two vars. additional to 7th ed. 535) alter name to C. integcrrimns. 539. Here the name itself represents the 535 a of the 7th ed. My own leaning would be to retain in this case a. either as "crenata," or a. genuinus in all cases where the type-form may cause confusion by not so being represented. Still, it really amounts to want of taking care to urge that any difficulty can result from my writing and asking a correspondent for 539, Sth ed. ; naturally, if I wanted other than the type, I should add b or c, as the case might be. 541. Here c may well represent 537 c of the 7th ed. ; the alteration in name really means nothing, as one might add a dozen varieties (if of any use) from old books. 548 and 550. Professor Babington combines these two plants ; the mistake in the 8th ed. is putting 549 between them ; the numbers really ought to be trans- posed : 549 to 550, then 550 to 552 would represent a graduated series. 562 should be S. roseum, Scop. 571, alter authority to " Linn." 576/; is a form with a decided stem, which I have seen more developed in rotiuidifolia. 5S2. Here the 509 b of 7th ed. is omitted ; it is really only a./, differing in the direction of the fruit- lobes. 587^ (authority should be " Guss."), is a/, with very short hairs closely packed over the surface. 593 has two vars. added — b and c. Hausknecht. in his monograph of the genus, places them as hybrids, giving several others as British ; this is a genus that will repay collectors, if good specimens with roots are gathered. {To be continued.) REVELATIONS CONCERNING THE BASS {LAB RAX LUPUS). By W. August Carter, Of the National Fish Culture Association. DURING the existence of the late South Ken- sington x\quarium, I made some. observations upon the bass {Labrax lupus), specimens of which were exhibited there measuring two feet in length and under. They were captured off Southwick, near the shore. The larger specimens attracted considerable attention from visitors to the late Colonial and Indian Exhibition, where they were regarded by many persons, uninitiated in things piscatorial, as salmon. HARD WICKE ' S SCIENCE- G OS SIP. Gi This erroneous impression is commonly shared, and can readily be accounted for by the fact of the tout ensemble of the bass, resembling closely that of its lordly confrere. On this account, I have known un- scrupulous fishmongers to dispose of the former to unwary customers in place of the latter. The habits of bass afford a very interesting study. Their dignified appearance when full grown earns them the respect and admiration of all visitors to Fig. 27. — The Bass (reduced). aquaria where they locomote backwards and forwards, unconscious of the admiring glances bestowed upon their silvery forms. But, as we are well acquainted with their characteristics, I shall proceed to record the result of my observations upon their habits and proclivities, which point conclusively to the extreme hardihood of their constitutions. In confinement bass are naturally not so voracious as Fig. 2S. — Head of Bass. in their normal sphere, but their appetites are neverthe- less very keen when living under artificial conditions. On first being admitted to the aquarium they abstain from food entirely, as they also do at certain seasons of the year. When once induced to feed at the out- set, they exist many years in an artificial state, but if at the end of eight days they reject their food, death ensues shortly afterwards. They can be accustomed to a varied diet, including meal, but mussels is the best kind of food upon which to feed them in cap- tivity, onisci and Crustacea, their natural sustenance, being difficult to procure regularly. They are cap- able of domesticating themselves to a variety of con- ditions, and changing their nature and food as well as the coloration of their body. In captivity the irides become more silvery, and the bluish tints upon the back lighter in hue. It is stated that bass thrive under fluviatile con- ditions. This, however, all depends upon circum- stances. On several occasions I .turned a few fish into fresh water, but did not succeed in maintaining them longer than six days. They became languid and thin in appearance, refusing to touch the various foods that I placed in their tank. In brackish water the case is different ; they frequently repair thither in their natural state when following their prey. There is no doubt that if the ova were hatched, and the fry reared in fresh water, they might be permanently naturalised thereto, in fact we are told by Columella that this was done by the ancient Romans with success ; but on the other hand, it would be extremely difficult to acclimatise them to a fluviatile existence after being reared in saline waters. I find that bass possess extraordinary vitality and powers of endurance. They are able to live more than three weeks in stagnant water, unlike their relation the Perca fluviatilis, which requires plenty of oxygen. The respiratory organs of the bass are of a high order, for until the last few days of their death under the con- dition described, they did not rise to the surface of the water to obtain air, which is the practice of most fish when deprived of oxygen. The gill-openings of bass are small, which may account for their being able to support life so long upon a meagre amount of oxygen. During their existence in stagnant water the bass moved less actively, but otherwise there was no indication of loss of vitality. Another proof of their powers of endurance is forth- coming in the following facts. I have noticed large specimens of bass sicken for death eighteen days before the event took place. An instance of this came before me a short time since, upon the arrival of several of these fish at South Kensington. Finding that they abstained from food, I examined them carefully, and by comparing their movements with other speci- mens, I noticed they seemed very weak. Their motion in the water was indefinite : they sometimes moped in corners of the tank and did not disport themselves upon the shingle at the bottom thereof, as their com- geners do when in good health. At the end of the first week they exhibited a tendency to change their attitude in the water from horizontal to vertical, until they rested upon their tail. This was a sure sign of speedy death, but they lingered on, nevertheless,, remaining stationary in the water, but on no occasion partaking of food. I continued to watch them closely for two weeks longer, thinking there might be a possibility of their recovery, but my hopes were 62 HARDWICKE'S SCIENCE-GOSSIP. not realised, one being found apparently in a lifeless condition at the bottom of the tank one morning at the end of the three weeks of its indisposition. On examination, I found no signs of life in it, and as it was required for the purpose of preservation in spirits, I desired the attendant to place it in a dry receptacle for six hours before operating upon it, in order to preclude the possibility of the slightest particle of animation being present. At the end of that time the fish was removed, and having filled a glass jar with spirits, I commenced to place the fish therein, head foremost. No sooner, however, did it come in contact with the spirits than it revived and wriggled about violently in the jar, insomuch that it upset the liquid. This incident fully confirms the result of the experiment tried some time since by Mr. W. Oldham Chambers, F.L.S., who restored carp on the point of expiration by the means of brandy. In the case before us we have a remarkable evidence of the hardihood of fish, serving to show that, although they may exhibit every sign of death upon outward examination, there is still animation within for some time after they grow stiff, which is capable of revivification, by the potency of a stimulant. On this account every effort ought to be made by anglers and others to takesuddenand effective methods of depriving them of animation, instead of allowing them tolinger in the pains of death on being captured. The spark of life that was accidentally kindled into a flame by means of the spirits infused into the bass, must have indeed been small, considering the length of time the fish had been kept out of water. In further support of my statement respecting the hardihood of bass, I would mention that they are capable of existing in water having a temperature of 300. This is noteworthy, as they disappear from view in their natural state during the winter, retiring into the deep water of warm locations. In the summer they emerge from thence, and approach the mouths of rivers where they usually deposit their ova. Aristotle, who was doubtless a great authority on fish, mentions that bass breed twice in one year ; this statement, however, is not correct. Doubtless it was inspired by the fact that bass sometimes yield their ova in two or three instalments, which I have known them do during a period covering two months. Again, con- sidering the large number of ova extruded at one time, it would seem impossible for them to repeat the supply twice in a year ; besides they require a warm temperature in which to spawn, therefore that they could not breed in the winter as well as the summer. It is to be regretted that the bass does not enter more freely into our list of dietaries. Provided it is quite fresh its quality is very good, but when three days old its flavour becomes impaired, being extremely oily. If, however, it was caught in larger numbers I feel sure it would become popular as a food fish. In the time of the ancient Greeks and Romans it was highly esteemed as an article of food, and attracted great attention in the writings of Aristotle, Ovid, and Pliny, while in the mosaic group of fish disinterred at Pompeii it is prominently depicted. One cause for their scarcity in the market, is the difficulty that exists in capturing them. There are few fish more crafty than the bass, and few requiring more elaborate fishing-engines or more skill in mani- pulating them. Like the grey mullet, they can best be taken by working the seine-net near the shore ; even then they effect their escape in a most cunning man- ner. They are evidently able to discern the presence of the net and avoid it accordingly, judging by the way which they dive beneath it to evade capture. Bass, therefore, are not popular with fishermen, who admit they are too wary for them, and cost more trouble and expense in catching than they are worth. Hence the paucity of the supply in the market, and the glut in certain parts of the vasty deep. For a marine game fish commend me to the bass, which affords almost as much sport as its dusky fluviatile congener of the United States. From rocks, boats or pier-heads, they may be taken by the means of rod and line, and I have, on various occasions, witnessed them landed at flood tide by means of an artificial dead or live bait. GOSSIP ON CURRENT TOPICS. By W. Mattieu Williams, F.R.A.S., F.C.S. SNOW IN AUGUST— We had some curious weather last year in England, but the meteoro- logical bulletin of the Royal Observatory of Brussels beats our record. On the 10th of August, at about 3.20 P.M., there was a fall of snow mixed with rain at Turnhout, in Belgium, and on the 3rd and 4th August there were white frosts at Maldegehm, in Flanders. The same on 12th, in the south-east of Belgium, There was a very severe frost on 7th July, which did considerable damage to the crops over a large area of country. The Steering " Instinct." — The migration of birds across the sea has suggested many specula- tions, some of them rather wild. How do they steer? Formerly there was no difficulty in solving this or any other problem of the kind. They were "guided by instinct." Instinct, like Mesopotamia, was a " blessed word" among the old naturalists ; it covered every difficulty. Subsequently " inherited memory" was modestly suggested, and recently it has become almost as blessed as instinct in settling everything. In his day Jack Falstaff said, "instinct is a great matter ; I was a coward upon instinct." If he were living now he would say, " heredity is a great matter ; I was a coward upon heredity." I have already advocated a much simpler explana- tion, viz. that the birds select narrow channels, and HARD WICKE' S S CIENCE- G O SSI P. 63 having great powers of vision, and the means of taking in a very large field of view, simply see the sunward land on the other side, and fly towards it. The difficulty here is merely a question of degree, whether or not some of the channels actually crossed are too wide for this. In " Nature," November 3rd, of last year, is a letter from Mr. Warde Fowler, describing the migration of swallows on the south coast of England. This shows that they take long journeys from west to east in search of a narrowing part of the channel. An officer of the German Navy, Captain Sebelier, has recorded some facts that lessen this difficulty. The islanders of the Marshall group in the North Pacific Ocean make long voyages in their canoes towards islets that are far beyond their vision-reach, and do this without any astronomical aid. From twenty to fifty canoes start together and keep within signal- reach of each other, and thus a large extent of sea is under survey. They advance until the islet is sighted by one or the other of the canoes. When such is the case, that one takes the lead, and the rest follow in accordance with the signal. That birds do signal each other is well established. May not the migrating birds guide each other on this principle ? The Marshall islanders rest at nightfall, but the birds fly so rapidly that daylight is long enough to serve them fully in covering the widest of their transmarine journeys. Nevertheless they some- times perish. I witnessed an example of this on the coast of Greece, near Cape Matapan. Had sailed from Malta in a small schooner in the spring, and encountered a severe gale. A number of swallows and martins settled in the rigging after the gale, and were so exhausted that they made no attempt to escape when we took them in our hands. They all died in spite of our attempts to aid their recovery. They appear to have been blown from their course by the gale. Caprices of Lightning. — We are told that an electric discharge follows the line of least resistance, and lightning conductors are placed accordingly to entice the discharge to follow an easy and harmless route. It does so usually, but not always. In the "Bulletin de la Societe Vaudoise des Sciences Naturelles " (No. 95), M. H. Dufour narrates some remarkable exceptions. A storm coming from the West passed over some gasworks and tall poplars without any discharge, but wrecked a house lying just below them on the leeward side. Again, at Penthalaz, the spire of a church was spared, while a house near to it was struck. It may be that in these and similar cases the cause of the discharge was nearer to the horizontal than to the vertical, not from a cloud to the earth, or vice versd, but between two beds of air or vapour lying at nearly the same elevation. We may frequently see discharges taking place between two clouds that are both at nearly the same elevation, and it is therefore not improbable that similar differences of potential may exist between columns of air near the ground at times of violent atmospheric disturbances. The Raising of Egyptian Monoliths.— As some of these reach a height of one hundred feet, and weigh some hundreds of tons, the question of how they were raised opens many speculations. One of the most recent of these is by M. Arnaudeau, who suggests that the obelisk being placed horizontally with its base towards the pedestal, a circular water- tight enclosure was raised equal in height to the obelisk. Then blocks of wood or other floats were fixed to the upper part of the obelisk and water was let into the enclosure, whereupon the monolith rose gradually to the upright position, and, being partly sustained by the water, was easily handled for adjustment on its intended base. This reminds me of a contrivance attached to Lord Rosse's great telescope at Parsonstown, with which I was not acquainted until I saw it in operation, and which may be equally new to most of my readers. The speculum at the object end is of course very massive, and demands a counterpoise. This is obtained by hanging heavy weights from the eye end. But the leverage at which these weights act neces- sarily varies according to the inclination of the tele- scope. When it is pointed nearly to the vertical this leverage is very short, and it increases as the great tube turns towards the horizontal. Therefore, in this case, the counterpoising weight requires gradual diminution. This is obtained by the aid of a deep water-trough, into which the counterpoise weights gradually dip as the eye end of the telescope descends, and thus their weight is first partially sustained by the water as they dip into it, and then fully sustained when they rest on the bottom. One weight succeeds another thus, and by skilful adjustment of this gradual lightening, the balance of the great tube is maintained at all inclinations. Freezing Water-pipes. — "Nature" tells us that the architect who designed the new Medical School in Paris took so little pains about the distri- bution of the water-pipes that in . very cold weather the laboratories for physiology, bacteriology, experi- mental pathology, &c, are wholly deprived of water. It is by no means necessary to cross the Channel to find examples of similar ignorance of the elementary principles of science among architects and builders. Now that there are so many empty houses in and around London and other great towns, and the competition for tenants is consequently very keen, the remedy is in the hands of intending tenants. If they firmly refuse to occupy any house the water-pipes of which are imperfectly protected from exposure to frost, and unprovided with the means of emptying them when frost is threatened, a change will soon 64 HARD WICKE'S SCIENCE- G OS SI P. come about. The expense, mischief, and annoyance due to the bursting of water-pipes in a house is a serious tax, and should therefore be appraised as a heavy discount on the rental value of the house. The Philosophy of Hair-curling. — According to a contemporary, "it is not generally known that the reason why hair curls when wound on a hot iron, is that the moisture on the side next the iron being evaporated by the heat, the cells in that part approach each other more closely, and this shrinking of one side causes the bend or curve." This explanation affords presumptive evidence that the writer is a young man, or at least young compared with myself. He was not flourishing when I went to the dancing- school, and under the mandate of imperative custom had to go to the hair-dresser before presenting myself at the "assembly-room." They did not enforce hair curling on " breaking-up " day at his school as at the "Academy for Young Gentlemen" where I was taught to regard all books as instruments of torture, and to hate them accordingly. Had he endured such experience he would have known that each particular hair was doubly or trebly twisted, and on completion of the twisting a comb was inserted between the curl and the scalp, and the hot tongs held for some time with the twisted hair in position, quite long enough for the heat to freely pass through a hair's breadth. The force of the final twist which I so painfully remember was a result of the operator's belief, founded on much experience, that the whole operation depended upon a certain degree of mere mechanical rigidity of the material operated upon which induced it to retain for a time any form into which it was forcibly restrained and maintained while hot. The recondite explanation above quoted does not cover the action of cold curl papers. The Mutability of Species. — In the Transac- tions of the Manchester Microscopical Society of last year is narrated (in the President's Address) an interesting account of change of species. In the neighbourhood of the Black Sea were a couple of lakes separated by a dam. The larger and higher of these contained 4 per cent, of salts, and in it Artcmia salina were living there in great quantity. The smaller and lower lake held in solution as much as 25 per cent, of salt and contained no artemioe. The dam between the two lakes was accidentally burst in 187 1, the lower lake was thereby greatly increased in size, and its salinity reduced to about S per cent. Many of the artemia; carried down with it died and many survived. The lower lake now began to evaporate, and the strength of the solution to increase. In the summer of 1872 the salinity had risen to 14 per cent., in the summer of 1873 to 18 per cent., in August 1874 to 23J per cent., and in September of the same year to 25 per cent. A Russian naturalist, Schmankewitsch, fished out and examined specimens of the artemia? at intervals during the three years, and found that as the strength of the solution increased, the artemise gradually lost the specific characters of Artemia salina and acquired those of Artemia Miilhauseni. The tail lobes gradually became shorter, and the number of setse diminished, until at the end of the third year all the artemiae were converted into typical Artemia Mulhauseni. The reverse experiment has been performed artificially. By gradually diluting the water Artemia Mulhauseni were reconverted into Artemia salina, and, by pushing the dilution still further, not merely a specific, but a generic change has been effected, the latter being converted into the fresh-water genus Branchipus which is of larger size and in many respects different. I remember well when the immutability of species was a sacred dogma, one of the articles of faith of the orthodox naturalist. I had some warm debates on the subject just after the publication of "The Vestiges." If an instance like the above was brought forward and could not be denied, the whole fabric of previous specific definition was abandoned, and the new species was described as a "variety." One such instance which I remember was that of our common wheat, which was shown to be derived from another genus. Accordingly generic definition was abandoned and specific differences bounded over in a wide leap, the two genera were converted into mere varieties. Thus the controversy became closed by the verbal device of defining a species as that which cannot be changed into another species, ergo species are immutable. What extraordinary change has since occurred among naturalists ! They themselves are no longer of the same species as formerly, and have even changed their generic name to that of " biologists." In contemplating this example of scientific evolution, let us not lose sight of the moral it conveys. Let us struggle to avoid all scientific dogmatism, and to fre- ourselves from the fetters of mere fashion in science, or what I have ventured, very impertinently, to describe as " scientific millinery." ASTRONOMY AND METEOROLOGY. By John Browning, F.R.A.S. AT the meeting of the Royal Astronomical Society, held on the 13th of January, Father Perry read a paper on the state of the solar surface during the year 1887, and gave an account of observations which he had made on 259 days at the Observatory of Stonyhurst. The number of days he had been able to observe the sun proved that the weather had been exceedingly fine in that part of England. From January to April, 1SS6, the solar surface was free from sun-spots ; but at the beginning of May, HA RD IVICKE'S SCIENCE- G OSSIP. 65 Rising, Southing, and Setting of the Principal Planets at intervals of Seven Days in March. Mercury 2 .' D. 4 11 iS 25 Rises, h. m. 6 15M 5 44M 5 23M 5 iom Souths. h. m. O I A II I3M IO 42M IO 27M Sets, h. m. 5 47A 4 42A 4 IA 3 44A Venus $ . A 4 11 18 25 5 35M 5 29M 5 20M 5 I2M IO SM IO I2M IO iS.M 10 24M 2 35A 2 55A 3 i6a 3 36a Mars <? . J 4 11 18 25 9 45A 9 I5A 8 43A 8 6a 3 7M 2 39M 2 8m 1 34M 8 25M 7 5§m 7 28M 6 57M Jupiter ¥. .] 4 11 18 25 1 13M 0 48M 0 21M 11 49A 5 27M 5 im 4 34M 4 2M 9 41 M 9 14M 8 47M S 19M Saturn I?. .] 4 11 iS 25 1 20A 0 51A 0 23A 11 54M 9 i8a 8 49A 8 21A 7 53A 5 20M 4 5iM 4 23M 3 56m 18S6 (which seemed at the time to mark the end of minimum period), there was a sudden outbreak. Since that date, however, there had been two tranquil periods, one extending from September 22nd to December 8th of 1S86, and another from January to April, 1887. In December, 1887, the spot area had been larger than in any month since May, 18S6. Mr. E. J. Stone read a paper on observations of the moon's place, made at the Radcliffe Observatory in 1887. In this paper Mr. Stone showed that the difference between the moon's observed and tabular place now amounted to fifteen seconds and eight- tenths. This difference is apparently due to a change in the length of our day. Mr. Bryant suggested that the opposition of the small planet Sappho would afford an opportunity for determining the solar parallax, by comparing photo- graphs of the planet and the neighbouring stars taken at different parts of the earth, or morning and evening photographs of the stars taken at an equatorial ob- servatory. The Astronomer Royal read a paper on the spectroscopic observations of stars in the line of sight. From a series of measurements of the position of the F line in Sirius, he inferred that there was an orbital motion of the star around some dark body in its neighbourhood. On March the 4th, Mars will be stationary at 2 hours after. March 20th, the sun enters Aries, and Spring commences at 4 hours morn. In this month there will be no occultation of interest. In March Mercury is a morning star. Venus is a morning star. Mars is in Virgo and rises late in the evening. Jupiter is nearly stationary in Scorpio near Antares. Saturn may be seen near the meridian from 8 hours to 9 hours in the evening. Meteorology. — At the Royal Observatory, Green- wich, the lowest reading of the barometer for the week ending 14th January, was 30*26 in. at the beginning of the week, and the highest 30*53 in. on Tuesday morning. The mean temperature of the air was 38*1 deg., and O'l deg. above the average. The general direction of the wind was south-west and east. Rain fell on Thursday to the amount of 0*02 of an inch. The duration of registered bright sunshine in the week was O'O hour, against 0*5 of an hour at Glynde Place, Lewes. For the week ending 21st January, the highest reading of the barometer was 30-48 in., on Wednesday evening, and the lowest, 29*68 in., at the end of the week. The mean temperature of the air was 34*7 deg., and 4*1 deg. below the average. The general direction of the wind was easterly, until Thursday afternoon, after which it was south-westerly. Rain fell on Saturday, to the amount of o*2i of an inch. The duration of registered bright sunshine in the week was 2 "5 hours, against 12*3 hours at Glynde Place, Lewes. For the week ending 28th January, the highest reading of the barometer was 30*28 in. at noon on Tuesday, and the lowest 29*66 in. on Thursday morning. The mean temperature of the air was 407 deg., and 0*9 deg. above the average. The general direction of the wind was north-westerly. Rain fell on two days of the week, to the aggregate amount of o*io of an inch. The duration of registered bright sunshine in the week was 3*0 hours, against 17*6 hours at^Glynde Place, Lewes. For the week ending 4th February, the lowest reading of the barometer was 29*08 in. on Tuesday afternoon, and the highest 30*15 in. at the end of the week. The mean temperature of the air was 33*7 deg., and 6*8 deg. below the average. The direction of the wind was variable. Rain or melted snow was measured on three days of the week, to the aggregate amount of 0*17 of an inch. The duration of registered bright sunshine in the week was in hours, against 12*6 hours at Glynde Place, Lewes. For the week ending February nth, the highest reading of the barometer was 30*15 in. at the begin- ning, and the lowest 29*26 in. at the end of the week. The mean temperature of the air was 43*6 deg., and 3 *8 deg. above the average. The general direction of the wind was westerly. Rain fell on four days of the week, to the aggregate amount of 0*26 of an inch. The duration of registered bright sunshine in the week was 1*8 hours, against 5*5 hours at Glynde Place, Lewes. The continued deficiency of rain is becoming most serious. 66 HARDWICKE'S SCIENCE-GOSSIP. In March the isotherms run across England in a North-Westerly direction. The mean average tem- perature for the month at Devonport and Plymouth is 450. From Swansea to Dorchester it is 44°. On a line drawn through Birkenhead, Warwick, Oxford, London and Deal it is 430, while at Lancaster, Burnley, Sheffield, Lincoln and Norwich it is 420. The average rainfall in March, for the greater part of the South Coast, varies between one and two inches. On the East Coast it is only one inch, while on the South-West and West coast it varies between two and three inches. PAPERS ON DRAGON-FLIES. The Metamorphoses of the Odonata. By W. Harcourt Bath, Author of "A Synopsis of the British Odonata" etc. Chapter I. — Introduction. THERE is probably no group or section of insects whose true position has given entomo- logists more trouble to ascertain than the Odonata or dragon-flies. Under the old Linnean system of classification, insects are arranged according to some structural resemblance which they bear to one another in common, thus the character of the wings represents the principal factor. This method, though it un- doubtedly holds good in the majority of cases, fails entirely to assign a proper arrangement of that composite order known as the Neuroptera or nerve- winged insects. Now the majority of the Neuroptera, it will be admitted by all, resemble one another, so far as the structure of their wings is concerned, but a criterion of far greater importance is presented in the fact that while two large sections of the order, namely, the Planipennia (or true Neuroptera) and the Trichoptera (or Caddis flies) possess complete or perfect metamor- phoses, another large group, known as the Pseudo- neuroptera (which includes the dragon-flies, day-flies, stone-flies, and their allies), possesses incomplete or imperfect metamorphoses. This vast distinction just pointed_out applied to our present knowledge of the laws of evolution, ought to be sufficient to separate the two first-mentioned groups from the last one by a wide chasm, without any reference whatever to structural affinities or superficial resemblances. In order, however, to expel (as it were) the Unionist party from its only stronghold, a very powerful structural separatist doctrine has com- paratively recently been promulgated by several eminent entomologists (the Home Rule Party?) to the effect that the formation of the mouth * in the Pseudo-neuroptera, together with the very general presence of pointed styles or filaments at the ex- tremity of the abdomen,* bears a remarkable ana- logical resemblance to the Orthoptera. This, considered in conjunction with the much more important fact, that the metamorphoses of the Pseudo-neuroptera are similar to those of the Orthoptera, effectually precludes the practicability of the former ever again forming a natural alliance with the Neuroptera. These considerations have even induced some modern writers f to unite the Pseudo-neuroptera with the Orthoptera— promoting the former group to the rank of a sub-order. Still more recently other writers have again reverted to the former system, but they offer no substantial reasons for the lines which they have adopted. + Thus the Pseudo-neuroptera have been enacting the typical bat in the amusing fable of the battle between the beasts and the birds. With the whole facts of the case now displayed before us, it is not difficult for any one to determine the true position of the Pseudo-neuroptera. They may, without any hesitation, be proclaimed to be connecting links between the Neuroptera and the Orthoptera, for while they cannot be attached to either group, by reason that they partake to a certain extent of the structural characters of both, their metamorphoses, which resemble those of the Orthop- tera, point to their being more closely.connected with the latter order. But, except in so far as is consistent with the object in view, it is not my intention to give an exposition of the biological position of the Odonata. I have written this and the succeeding papers to give a brief but clear outline of their metamorphoses, in order to act as a stimulus for further observation and inves- tigation on their behalf, for hitherto comparatively very little has been recorded in connection with dragon-flies. It will perhaps be necessary for me, in the first instance, to give some of the most important struc- tural characteristics by which the insects under our consideration may be readily distinguished from allied groups of the Pseudo-neuroptera. The imago possesses a large head, which is armed with a powerful and complicated mouth. It has a pair of very large compound eyes (which are con- tiguous in some groups and remote in others), con- sisting of a great number of lenses or facets. And in addition there are three simple eyes, called Ocelli or stemmata, which are situated on the crown of the head, and arranged either in a straight line or in the shape of a triangle. The antennre are awl-shaped. * See Brulle, M. Aug, "On the Mouth of Libellulida:," in ' Annates de la Societe" Entomologique de France." Paris, 1854. * See Westwood, J. O., " An Introduction to the Modern Classification of Insects," 2 vols., 8vo. London, 1840. Libellu- Ut See Dales', Vs., « Cassell's Natural History," 6 vols., 8vo. London, 1882. Odonata, vol. vi. pp. 143-146. „ t SeeKirby, W. F., " Elementary lext Book of Entomology. 8vo. London, 1885. Odonat.., pp. £8-91. HA RD WICKE' S SCIENCE- G OSSIP. 67 The thorax is generally stout, and the abdomen comparatively long, being extremely slender in certain families. At the apex of the latter are situated two pairs of forcipated, or leaf-shaped appendages, varying considerably in form in the different species and also to a less degree in the sexes. The wings are elegantly veined or reticulated, and both fore and hind pairs are equal in size. In repose they either rest horizontal or erect, the posterior pair never being folded.* The metamorphoses of the Odonata, as has been previously mentioned, are incomplete or imperfect ; that is, the larva differs very slightly in structure from the imago or perfect insect, and the pupa is lively with the exception of a very brief period previous to undergoing the final stage. Dragon-flies are amphibious creatures, in all the earlier stages of their existence they reside in the water of streams, ponds, and lakes. No species has hitherto been discovered to inhabit salt water, though certain kinds have been found in brackish water, f a very important fact indeed, since it may prove eventually to be a valuable clue towards a solution of the origin of the Odonata and likewise to the elucida- tion of their evolution. One of the most wonderful facts in connection with the economy of these highly specialised insects is their mode of breathing in the water, which is not (in the Libellulina) by means of branchiae as is the case with many other aquatic insects, but is internal — but we will reserve the discussion of this for another chapter. In the next, we will commence to consider the metamorphoses of the Odonata in detail. {To be continued.) SCIENCE-GOSSIP. " My Telescope " is the title of a little astronomi- cal work by "A Quekett Club-Man," whose kindred volumes on the microscope have been so successful. It will be published in a few days by Messrs. Roper & Drowley. Silk -worm Cocoons. — It would be interesting to know whether the brown silk, exhibited by Mr. E. B. Poulton and recorded on page 21, is liable to become the usual bright yellow on exposure to light for a long period.—^. C.D.B. Death has been very busy lately in the ranks of the foremost scientific men of all countries. Many names will henceforth be removed from the lists of living, to those of historic, celebrities. Among them are the * For further and more complete particulars of structural characteristics, see Westwood, J. O., "An Introduction to the Modern Classification of Insects," 2 vols., 8vo. London, 1840. Libellulida^, vol. ii. pp. 34_4°- f See Kingsley, John Sterling, "The Standard Natural History," 4 8vo. Boston, 1884. Odonata, vol. ii. p. 147 (Uhlers quoted). following : — Prof. Hayden, late director of the U. S. Geological Survey, at the comparatively early age of fifty-eight ; Dr. Asa Gray, the distinguished American botanist, at the riper age of seventy-seven ; Mr. Waterhouse, late keeper of the Geological Department of the British Museum, in his seventy-eighth year ; Professor De Bary, the celebrated botanist and fungo- logist, at the age of fifty-seven j and others of less note. Dr. G. J. Romanes has been elected to the Chair of Fullerian Professor at the Royal Institution, and intends occupying the whole of his three years of office delivering lectures on " Before and After Darwin." Mr. J. E. Harting has been appointed Assistant Secretary to the Linnean Society in place of Dr. Murie. There is nothing new under the sun ! The other day there was dug up among other long-buried curios at Pompeii, a case containing a complete set of surgical instruments, many of which are said to be closely similar to those used at the present day. The medical art is evidently both very ancient and very conservative. It was the last French war which originated the beet-sugar manufacture in France. The sugar-loving Frenchmen could not get it from the West Indies. Within a very short period a sugar beet was artificially selected, and in our time this beet has so developed its saccharine qualities that it produces nearly twice as much sugar as it did in Napoleon's time. But the Germans also took up beet-sugar manufacture, and they have beaten the French even on this field of war. Thanks to their improved methods of extracting the sugar and molasses from the beet-root, they can now obtain nearly n|lb. from 100-lb. weight of beet, so that the cost of the sugar is now reduced to id. per lb. A well-KNOWN New York physician has just published the sort of discovery which Lord Lytton would have made a novel out of. An aged Polish count, formerly professor of languages and a famous Oriental scholar, died in the hospital, and Dr. Rookwood had occasion, in conjunction with other experts, to make a microscopical examination of a certain part of the cerebrum. They noticed a peculiar set of markings, which took the form of Egyptian and Chinese hieroglyphics. These were amplified to a magnitude of 3000 diameters, and the results shown to another Oriental scholar, who declared them to be true characters in the Ethiopic, Syriac, and Egyptian languages. Dr. Rookwood suggests that his discovery will lead to extracting from the dead their literary achievements as well as their "suppressed opinions." 68 HA RD WICKE'S SCIENCE- G OS SIP. The International Geological Congress of all the nations employing geological surveys is fixed to meet in London on September 17th of the present year, under the presidency of Professor Huxley. This congress assembles in a different country every three years. This will be the first time it has met in England. A NOVEL and important invention for the manu- facture of copper-tubing has just been made by Mr. W. Elmore. He slowly deposits the copper by electrolytic action in a bath upon an iron mandril, which is kept rotating there. The copper is de- posited in thin films, and as it is thrown down it is compressed by an agate burnisher into a hard and solid mass, of such great tensile strength that it has sustained a breaking strain of forty tons to the square inch. An American inventor, Mr. A. P. Wade, has brought out a combined potato-digging and harvest- ing machine, which not only ploughs the potatoes out of the ground, but also separates them from soil and dirt, and either transfers them to a waggon or arranges them in rows, as may be desired. Hitherto it has been laid down by physicists that the dull red rays of light are the first luminous rays to appear, but Mr. Weber has just shown that the filaments of solid carbon, gold, iron, and platinum give a grey glow first, and at a temperature below that of "red heat." Some very suggestive and important experiments to chemists have been made by Professor Meyer, of Gottingen, on the ultimate atoms of carbon. He thinks that the atoms of carbon are spheres, each surrounded by an "ether shell," which latter forms the seat of its well-known four-coupling (quadri- valency) power. He imagines the "four-coupling" powers have some electric centres of connection, which he calls " electrules." Our knowledge of the sun is increasing, thanks to the new spectroscopes. Tire latest bit of scientific information thus afforded is that platinum is a solar element. Mr. W. E. Case has recently read a paper before the American Institute of Electric Engineers which is causing much attention. It is on the possibility of obtaining energy from carbon by electrical means without heat. Botanical Evercirculator about to be started. Members wanted. No charge. Address J. Hamson, editor, 19 Victoria Road, Bedford. The members of the Woolhope Naturalists' Club have contributed to the materials collected and arranged by the late Dr. Bull, of Hereford, on the birds of that district. The " Birds of Herefordshire " is therefore announced, price 5.?. The Natural History Society of Glasgow appears to have recently taken out a new lease of vigorous life, judging by the quality and character of the papers read. A Canadian naturalist says that the bee's sting is by no means used for stinging only, but is utilised in doing all manner of artistic work, in capping the comb, and infusing formic acid, by means of which honey receives its keeping properties. The sting is in reality an exquisitely finished tiny trowel, with which the bee rounds and caps the cells when they are brimful of honey. This explains why honey extracted before it is capped over does not keep well ; the formic acid has not been injected into it. We are sorry to have to record the death of the well-known botanist, Dr. J. T. I. Boswell (an old and valued contributor to SciENCE-Gossir). He is best known to many people as the editor of " Sowerby's Botany," to which he devoted twenty years of his life. The annual meeting of the Geological Society awarded medals as follows, for distinguished services in this special science : H. B. Medlicott, the "Wollaston"; Professor Newberry (New York), the " Murchison," and Professor H. AUeyn Nicholson (the well-known author) the " Lyell." During December and January Dr. J. E. Taylor delivered popular science lectures on geological, zoological, botanical and other subjects, to large audiences in various parts of the country, at Leigh ton Buzzard, Ipswich Museum, Wolver- hampton Literary and Scientific Society, Hadleigh, Southwold, Windsor, Lowestoft, Manningtree, Chelmsford Museum, etc. MICROSCOPY. Notholca SCAPHA. — I may perhaps be allowed to mention that I found these species in some abund- ance in this neighbourhood in October last. For some time after I met with it I did not know that it had ever been found in fresh water ; and this fact, together with the long oval shape described by Mr. Lord, led me to doubt whether I had not had the good fortune to light upon a new species. After a time, however, I found that a dead specimen closely resembled Mr. Gosse's second figure of N. scapha in " The Rotifera." Till then I had thought my speci- mens might belong to a species intermediate between A7", scapha and N. thalassia (not thallasia, as mis- printed in Mr. Lord's article). I sent some of the water in which the Notholca occurred to Mr. Gosse. In the first bottle sent he did not find any specimens of Notholca, thougli he did find an undescribed Furcularia, which was very numerous ; but in the HARDWICKE'S SCIENCE-GOSSIP. 69 second bottle he found " a vigorous specimen," of which he told me that he had had " capital protracted observation." He then mentioned to me that Mr. Lord had sent him specimens last May which were indistinguishable from JV. scapha ; and he considered my species also to be the same. The general aspect of my specimens certainly agreed better with Mr. Lord's figures than with Mr. Gosse's ; but I do not understand Mr. Lord's suggestion, that N. scapha might have been named from a dead specimen ; surely it is clear that Mr. Gosse's first figure was drawn from life. I did not find that the broad out- line was constant in dead specimens, and on the other hand I did find that the breadth of living examples varied considerably. The length, both absolute and relative, of the occipital spines also varies. I saw one specimen in which they were all unequal ; that is to say, they were not arranged in pairs, but each spine differed perceptibly in length from all the others. Most of my specimens came from a puddle at the foot of a coal heap, near a disused colliery. This puddle con- taineda number of lobster-pots, sardine-boxes, and old boots, and other refuse of the same kind. A quantity of floccose vegetation floated on the top ; and in the little heaps formed by this weed the Notholca found its food, which consisted chiefly, I think, of small diatoms. The action of the jaws in a healthy speci- men is remarkably energetic. My experience un- fortunately agrees with Mr. Lord's as to the short life of the species in captivity. It is curious that on the nineteenth of September last I found what I believe to be the same species in a 'shallow and rather muddy stream near here. I then found only two specimens, and have not been able to find any there since. My only reason for doubting the identity of this species is that I sometimes thought I saw a short, slender spine projecting from one side. But this spine, if it existed, was very much shorter than in Mr. Hood"s figure of N. spinifera ; and I never saw more than one spine at a time. The animals were too restless for satisfactory examination. — J. W. Blagg, Greenhill, Cheadlc, Staffordshire. Mounting Perishable Crystals Sections. — A mounting medium should be transparent and colourless, if possible, of an index of refraction having reference to the subject treated, and free from mois- ture. It must not be a solvent of the matters that it is employed to preserve. As media of this kind especially worthy of attention for mounting perishable crystals, or such as lose their polish or become opaque in Canada balsam, as well as in the air, Professor Johnstone of Johns Hopkins University, recommends the following: — (1) Finest gum copal dissolved in chemically pure absolute alcohol ; (2) Finest copal dis- solved in chemically pure absolute alcohol ; (3) Dam- mar resin dissolved in rectified spirits of turpentine. No heat should be used in making these solutions, and the resultant liquid should be very thick ; (4) Dammar resin dissolved in well-boiled balsam copaiba ; (5) Boiled Chian turpentine dissolved in boiled balsam copaiba ; (6) Dammar resin boiled until the rising scum becomes nearly dissipated, the remain- ing scum to be removed with a spoon. Section-Cutting.— The application of the terms "hard " and "soft" paraffin, as employed by W. B. H., is likely to be a little misleading, especially as the majority of microtomists are familiar with medical literature. The term " soft paraffin," or Paraffinum molle, is technically and officially applied in the "British Pharmacopoeia," and consequently in all works of Materia Medica, to a paraffin of a far lower melting-point than that so designated by your correspondent. It is the body popularly known as Vaseline. A paraffin imbedding wax of any desired melting-point below that of hard paraffin could readily be prepared, by melting together varying proportions of the official " Paraffinum durum " and " Paraffinum molle." These could readily be obtained from any pharmacist. — J. Oldham Braithivaite. Pond Dredging and Collecting. — In reply to your correspondent's query in the Science-Gossip for February [p. 45] as to the net to be used in collecting Rotifera, &c, I should advise him not to use a net at all. The best appliance with which I am acquainted is made by fastening a wide-mouthed glass bottle (such as a pomatum pot) to the end of a walking-stick, by means of a stout copper wire, which should be tightly whipped with strong thread and varnished. For more delicate work or for use in ponds, &c, comparatively free from weeds, a large sized test-tube might be substituted for the bottle and should be fastened to a short thin length of bamboo as follows : — Take a six-inch length of caoutchouc tubing, and make a cross cut three- quarters through, at about an inch from one end : then another at right angles to the first along the other five inches : the result is a short piece of tube with a five-inch slip of gutta-percha. The tube is slipped over the end of the rod, and the free end of the flap is pushed between the rod and the tubing, the test tube placed in the loop so formed and the slip drawn tight and fastened off. — Jno. Eyre. ZOOLOGY. The Lesser White-Fronted Goose {Anser erythropas, Linn.). — A goose identified as one of this species, and apparently a wild one, was shot near this town in January last. This bird not having been admitted into the British list, the capture is an interesting one, and I shall be pleased to give further information on the subject to any one who will apply tome. — W. Gyngell, Wellington, Somerset. 7o HARDWICKE'S SCIENCE-GOSSIP. Yellow (or Ray's Wagtail). — S. M. T. in Science-Gossip for January does not give the date when he observed Ray's wagtails on his lawn. If by "last month" he means November, it is possible they may have been grey wagtails (Motacilla flavd) and not the yellow species {M. rail). The latter is a migratory bird, and generally leaves us in autumn, whilst the former remains with us all the winter. I generally see a pair of grey wagtails at Christmas in Somersetshire (about thirty miles from Weymouth), beside the little stream running through my brother's farmyard. They are usually to be seen in the yard, or at the drinking place for cattle in the adjoining field. In the winter plumage the breast and under- pays are a beautiful lemon-yellow merging into white at the throat. In the summer plumage the male has a conspicuous black throat, which it entirely loses in winter. On the other hand, I must say that the yellow wagtail is also a common bird in the same district. This last summer one of my friends saved me two nests which his men cut out of a vetch field, and in the autumn they are exceedingly numerous and tame, running about quite unconcernedly among the sheep whilst the shepherd is pitching out the fold. The yellow wagtail too has been observed by Dixon to remain with us occasionally all through the winter, and the fact of its being seen on a lawn is more in accordance with its habits than with those of the grey wagtail. There is a striking difference in the species in the length of tail, that of the latter being from three-quarters of an inch to an inch longer than the former. As the lawn would probably not be "newly mown " after the month of October, I think it most likely that the ten birds observed by S. M. T. were a party consisting of two broods from the same parents making their way down to the sea preparatory to migration. — Robert H. Read. BOTANY. Carex FRIGIDA, All. — Dr. Macfarlane has kindly sent me for examination, the original specimens gathered by Mr. Sadler in Glen Callater, and along with them a sheet from Wight's collection, with two specimens of undoubted C. frigida on it — from " Clova Mountains ex herb. W. H. Campbell " — doubtfully named C. binervis, Sm., but either Dr. Greville or Professor Graham has written "I doubt this." Both Mr. C. B. Clarke and Mr. N. E. Browne consider these specimens C. frigida of Allioni.— A. Bennett. A Green Rose. — Last summer I came across a curious rose, a brief description of which may interest some of the many readers of your magazine. My attention was drawn to this flower, owing to its petals, as it then appeared, being unusually green, but it soon turned out that these seemingly green petals were the sepals of another and internal flower, which stood after its pedicel had fully developed, about one inch and a half above the lower flower. This lower flower seemed to be quite sterile, for its stamens bore no anthers, and they were unusually long and slender, and they very soon withered away, but the higher flower proved to be a good and healthy one, and seems to have made good the failures of its lower mate. — G. Rees. GEOLOGY, &c. A Relic of the Ages. — Discovery of Fossils. — An extraordinary discovery of fossils has just been made at Ilford. Some workmen who were at work extracting clay in the Cauliflower Brickfields came upon the bones of some large animal. When found, the bones of the head were almost perfect, and measured about seven feet round. The fossils were firmly imbedded in the clay, resting on a bed of sand, and from their appearance would lead one to suppose that the animal — presumably an elephant — had fallen head foremost to the earth and never again moved. The property has been used as a brickfield for about seven years, it having during that time been excavated to a great extent. Bones of animals have fre- quently been found, but a find of such an enormous relic of bygone ages is an unprecedented event. A New British Fossil Carnivore. — A curious little object, a small fragment of jaw with three molar teeth, was the subject of much interest at the last meeting of the Geological Society. It was found in the Red Crag of Suffolk, and Professor Boyd Dawkins has christened it Ailurus Anglicus. The singular thing is that the family of raccoons is Indian, and previously the remains of a fossil Asiatic gazelle had been found in the same deposit, showing a former terrestrial connection with India. Did the raccoons get to India from England, or did they come from the former country to these latitudes ? NOTES AND QUERIES. Yews. — Of ancient yews many authentic cases can be named. At Ankerwyke House, near Staines, there is, or was, a yew older than the Magna Carta itself, i.e. over 670 years old. This tree is stated to measure at three fiet from the ground 9 ft. 3 in. in diameter, and its branches overshadow a circle of 207 ft. in circumference. At Fountains Abbey, in Yorkshire, there are some yews probably more than 1200 years old, and to others an age from 2500 to 3000 years has been assigned. The baobab tree of Africa is estimated by Adanson at 5000 years, and the deciduous cypresses of Chapultepec, in Mexico, are considered to be even older. But it must be borne in mind that, although in temperate climates trees shed their leaves and renew them once a year, and therefore one layer only is formed, whereas in HARDWICKE'S SCIENCE-GOSSIP. 7i tropical climates, where many kinds of trees have two or three successions of leaves in a year, a correspond- ing number of layers will be formed. The method of ascertaining the age of an exogenous tree by counting the number of concentric rings visible would be absolutely correct, if one could be quite sure that observers provided against all possible causes of error. But it has been shown by Dr. Lindley that, in con- sequence of the extreme inequality in thickness of the annular layers of wood on the opposite sides of a stem, a person who judged of the whole age of a tree by the examination of the layers of the stunted side only would commit errors to the amount of 60 per cent, or more. — F. C. D. B. Castor. — I think Mr. Ingersoll has made a slip of the pen (or else there has been a printer's error in the brackets), in calling the secretion of the male of the musk deer, "castor ; " and there has been a further oversight in assigning to that animal a habitat in Africa. Castor is the secretion of the ano-preputial glands of the beaver {Castor fiber) of Europe, Asia, and America, the American being the least esteemed. If your contributor is referring to musk, that is the secretion of the preputial glands of the musk deer (Mosc/n/s moschifenis) of Central Asia. There is a musky secretion from the inguinal follicles of certain African antelopes, but this is not used as a drug. Antelopes of South Africa, Abyssinia, Nubia, Tripoli, Morocco and Senegal are known to emit this musky or sub-musky odour. — Viator. Croaking of Frogs. — Having kept tree-frogs myself, I was much interested in the note by M. R. in the February issue of Science-Gossip. My frogs were kept in an old aquarium specially fitted up for their requirements ; on no occasion, however, did I hear my pets croak, and they never entered water voluntarily. As they came from Germany, however, no doubt they partook somewhat of the phlegmatic seriousness of the proverbial German. I should much like to possess specimens of the species M. R. refers to, and would be exceedingly obliged if that gentleman would kindly inform me where, and from whom, they may be obtained. I always have under- stood that tree-frogs passed the winter in a torpid state, buried in the mud at the bottom of stagnant pools ; and also, that they deposited their eggs therein previously to leaving the water. My frogs were quite as voracious as those possessed by M. R., and would take prodigious leaps after their prey and alight upon it with unerring accuracy. My pets, however, never attained to a greater size than an inch in length, two of them were green and two brown, and they never changed their colour, only appearing a little brighter after a cast of skin. I had an old frog once who used to croak dreadfully, he lived in a conservatory adjoining the house, and his croaking could be heard quite plainly in the house. He never croaked, however, unless he could find a pan of water to sit in, but so surely as water was left about on the floor he would get into it, and laying his throat quite flat on the surface of the water would give forth such a series of croakings and gurglings as made one's blood run cold. — W. Finch, jun., 158 Arkivright Street, Nottingham. Ornithological Voracity. — It is not at all un- usual for birds to be suffocated whilst endeavouring to gorge food too large for them (Science- Gossip,