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made, colour being affected by the same towards the base generally showing pink or golden, and nearer the harder apex, blue and purple tints. Some species have hollow spines; such specimens are deeply furrowed longitudinally on the outside, and are generally too large to make perfectly circular sections to fall within a microscopic "field" of view, but delicately cut and ground; segments of such slices display such remarkable elegance and neatness of design, that when carefully illuminated, and the configuration of the parts studied, they at once impress the mind with their adaptability to purposes of artistic decoration. It is possible no class of microscopical presentations can be more suggestive to the designer of geometrical patterns, and under various conditions of light they are materially altered in appearance. Many parts with transmitted light show configuration, and but slight colour or substance; under the radiation of dark ground illumination they become totally different, and flash out exquisite translucent pearly lustres. With the polariscope, especially when the cutting is carefully selected for extreme thinness, but yet preserving the denser parts intact, the beauty is incomparable. Even mounted as purely opaque objects, under the radiance of the side speculum, porcellaneous specimens show a rare delicacy.

A minute examination of one of these sections recalls the rings and medullary rays of the stem of an exogenous tree, and their number and position (as in the tree) depends on the age of the spine and the part from which it is cut. In the centre is an open network slightly divergent, at intervals zones of larger deposits, calcareous tracery intervening, the whole cut up by equidistant structural radiations; illuminated with the paraboloid, what appear to be the larger "spaces," as distinguished from the general intersections, are seen of uniform substance and colour. A spine may be defined as a fluted spur of connective hard pellucid tissue, with interspaces filled with solid glass. Spines of the British Echini have no concentric rings, it is supposed in consequence of periodical shedding, while in tropical species in the course of growth, layers are added. crushed spine resolves itself into glass-like particles, transparent and brittle. A power of repairing fracture and injury has been observed, the vitality of the spine and its increase in size is maintained through a connective tissue at the base, and although the internal structure is apparently unprovided with vessels, reparation takes place, as long as the animal he living and the injured spine attached; many sections, especially when cut through the length, often reveal such interferences of regularity, obviously the result of injury, and recuperative power.

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An attempt was made by the writer to depict, in the second volume of Coles' " Microscopical Studies" (Methods of Research) one of these sections to illustrate appearances under four different modes of

illumination. The difficulty in preserving delicate line, with painting effects of colour bathed in light; supplemented by the more limited resources of even the best chromo-lithographer (a condition of things seen in the present subject) reduces such drawings, when printed, to mere semblances of the reality; but they offer, at least, sufficient inducement to direct attention to the general elegance found in these most popular of microscopical objects. Crouch End.

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THE VIOLET.

UY my sweet violet, a penny a bunch! is one of the familiar cries we hear every morning at this time of year (spring) as we hasten to our respective callings in London (and no doubt in other cities as well). It is a most refreshing sight, to any person who has the least spark of the love of nature, to look at the beautiful baskets of button-hole bouquets which meet our eyes in the different streets, but more particularly in the neighbourhood of the Bank of England and Royal Exchange. The city clerk on his way to his office, purchases a bunch of violets-places them on his desk, surrounded with his day-books, ledgers, and all the paraphernalia of a mercantile house: perhaps once or twice during the day, while his mind is engaged on the routine of his daily duties, the delicious perfume from his morning purchase causes him for a few moments to look up at these emblems of modesty and innocence, and awakens a train of thought of the days of his childhood, when he and his companions hunted for the fragrant flower among the green fields and hedgerows in the early spring.

But time flies; work must be finished; no leisure for such meditations; still those few moments have not been spent in vain : his brain has been rested by a change of thought, and he is enabled to go on with his work with fresh energy and vigour. Thanks to the little violet. This flower was held in high estimation by the ancient Greeks. A golden violet was offered as a prize in their floral games, and we are told in their fables that Ia, the daughter of Atlas, fleeing into a wood from the pursuit of Apollo, was through the power of Diana changed into a violet, which still retains the bashful timidity of the nymph, by partly concealing itself from the gaze of Phoebus in its foliage. The Greek name for this flower was 'Iov, said to have been given it because Iov the daughter of Inarchus, whom Jupiter transformed into a heifer, fed upon violets, or, as some mythologists state, sprung from her breath. The Athenians, we know from the writing of Anacharsis, had beautiful gardens attached to their country houses, in which they cultivated the narcissus, hyacinth, iris, and violets of different colours, likewise roses of various kinds. All these flowers were

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wreaths of fragrant violets, Covered with dust as if in summer."

Vitruvius, a celebrated writer, who flourished under Julius Cæsar, tells us that the flowers of the violet were not only used to adulterate or counterfeit the celebrated blue of Athens, but were also employed to moderate hunger, to cure ague and inflammation of the lungs, &c., and the blossoms worn as garlands were considered as a charm against falling sickness. The Romans used to put large quantities of violet petals into casks, and cover them with good wine; from this infusion they procured a drink called Violatum, which was only used on festive occasions. The petals of roses were also used in the same fashion, and called Rosaltum. Pliny gives a long list of the virtues of this flower. The ancients believed the seed counteracted the effects of scorpions' stings. The violet has been in all ages a favourite flower, and is recognised by the poets as the emblem of modesty and innocence. Spencer calls it the cool violet, and Shakespeare compares the soft strains of plaintive music to its perfume.

"That strain again; it had a dying fall.

O, it came o'er my ear like the sweet sound,
That breathes upon a bank of violets,
Stealing and giving odour."-Twelfth Night.

And again, the touching remark of Ophelia, who coloured all nature with hues of her own sad thoughts, "I would give you violets, but they withered all when my father died." Milton makes echo dwell amongst violets :

"Sweet Echo, sweetest nymph that lives unseen,
By slow Meander's margent green
And in the violet embroider'd vale."

From Googes' translation of that old work, the Popish Kingdom, we find that the violet was among the flowers used in the ceremony called "creeping to the cross" on Good Friday, and, no doubt, it was present in all the old floral usages of spring in "days gone by." Our old botanist Gerard mentions several kinds of violets in his Herbal, but the sweet violet he says has a great prerogative above all others, for one reason he states, "because they are delightful to look upon, and pleasant to smell too. They also bring to the mind the remembrance of all kinds of virtues. For it would be unseemlie for him that doth look upon and handle faire and beautiful things, and who frequenteth and is conversant in faire and beautiful things to have his mind not faire-but filthee and deformed." In the reign of Charles II. a conserve called violet sugar, or violet plate, was sold by apothecaries, and continually recommended by physicians to their consumptive patients.

This flower has been made the badge of political

feeling in France, the violet being the emblem of the liberal party. In 1814 many pictures were circulated in France which appeared to represent merely a bunch of most innocent violets, but a little scrutiny of the shadows cast by the violets enabled any one looking for such a thing to discover portraits of the first Napoleon and his wife and son-(vide "Flower Lore.") The violet was the favourite flower with Napoleon the first; and the Bonapartists, during the banishment of their chief to Elba, while plotting for his return, filled their snuff-boxes with violet-scented snuff, and when offering a pinch would significantly enquire: Do you love this perfume? and at the time when he was expected to return to France, they toasted his health under the name of Caporal Violetta or the flower that returns with the spring.

Botanically, the violet belongs to the order Violacea, which contains about a hundred species spread over the greater part of the globe, but is limited in Europe to the single genus Viola, containing several varieties, as the marsh violet (V. palustris), hairy violet (V. hirta), dog violet (V. canina)—(V. tricolor) heart'sease or pansy-all (except V. odorata) with scentless flowers. In all the British violets, except the pansy, the perfect flowers seldom set their fruit; but if a plant is examined during the summer and autumnal months, large capsules, containing fertile seeds, will be found produced by minute flowers almost without petals or

stamens.

It was the violet which induced John Bertram, a Quaker of Pennsylvania, and the friend and patron of Alexander Wilson, to study plants. He had employed his time in agricultural pursuits without the knowledge of botany, but one day he gathered a violet, examined its formation, and reflected upon it until he became so prepossessed with the flower that he dreamed of it. This circumstance inspired him with a desire of becoming acquainted with plants, he therefore learned for that purpose as much Latin as was necessary, and soon became the most learned botanist of the new world. The colour extracted from the violet by infusion affords the very delicate test called violet paper used by chemists for acids and alkalies, being reddened by the former, and rendered green by the latter. Syrup of violets is greatly used by confectioners for making confections, candies, &c., also by perfumers for scenting oils, pomades, and making Eau des Violettes. Large quantities of violets used to be cultivated at Stratford-upon-Avon for this purpose. The root, or

rather the underground stem, has a strong smell, particularly when dried, and its taste is acrid, bitter and nauseous.

Professor Burkman states, that in some parts of Gloucestershire the violet is considered unlucky to have in the house, the reason alleged being that these flowers "certainly brought in fleas." Probably the warmer weather of spring which ushers in the violet, said to be "a stinking flower" by the foxhunter, causes the troublesome little insect to be hatched.

Violets are cultivated on a large scale round London, at Twickenham, Strawberry Hill, Richmond, and other places on the banks of the Thames. They are usually grown under orchard trees, a position in which they thrive remarkably well. They are also grown in large quantities in some parts of Violet Kent, Surrey and Sussex, Pevensey, &c. culture is said to be a most lucrative industry. HAMPDEN G. GLASSPOOLE.

species. Perhaps no department of natural history has come more to the front lately than that of land and fresh-water mollusca. Mr. Adams is well known as a conchologist, and he therefore knows what he is writing about. Moreover, he also knows how to present his knowledge in a useful form. The present work, besides describing every species, its habits, localities, &c., gives an account of all the varieties, hints on arranging and preserving shells, &c.

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NOTES ON NEW BOOKS.

BIBLIOGRAPHY, Guide, and Index to Climate, by Alexander Ramsay, F.G.S. (London: W. S. Sonnenschein & Co.). This is in reality a magazine of systematic notes relating to climate, with digests of papers and books, &c., on the subject. The volume exhibits immense industry and research, and the student will save much time by using it as a reference book.

Edible British Mollusca, by M. S. Lovell (London: L. Reeve & Co.). The second edition of this nicely got-up book has appeared, illustrated by beautiful coloured plates, and containing a large number of recipes for cooking all our natural mollusca. The reader will be astonished to find what a number of recipes are available. There is a good deal of quaint reading in the work, and altogether it is one unique in this department of literature.

A Handbook of the Geology of Shropshire, by J. D. Mr. La La Touche (London: Edward Stanford). Touche is well known as a field geologist and ardent worker with the hammer, and he has laid all British students under obligation by bringing out this compendious little handbook of the geology of perhaps the most interesting geological county in Great Britain. It is a digest of all that is good and useful from "Siluria" to the last published paper of Callaway, Lapworth, Hopkinson, Maw, and others, besides the author's own original observations; and it is illustrated by twenty lithographed plates, containing above 700 figures of fossils from the Cambrian to the Old Red Sandstone inclusive.

The Microtomist's Vade Mecum, by Arthur Bolles Lee (London: J. & A. Churchill). This is a valuable book, especially to medical students who are diligent in the use of the microscope, as it describes all the methods of microscopic anatomy. It is intended, however, more for the instructed anatomist than the beginner, and therefore country doctors who wish to keep their "hand in" work they always loved, but have found little time to continue, will bail this little work with pleasure.

The Collector's Manual of British Land and Freshwater Shells, by Lionel E. Adams (London: George Bell & Sons). A beautifully got-up little manual, with exquisitely engraved figures of every British

FERTILISATION OF ORCHIS MASCULA. By EDWARD MALAN.

IN

Na back number of SCIENCE-GOSSIP (Aug. 1883, p. 181), your correspondent G. M. pointed out some errors into which I had fallen with respect to the fertilisation of O. mascula, and, when, in a subsequent number (Nov. 1883, p. 249), I asked him to favour me with his address, he did so at once with the utmost courtesy.

To this day, shame on me, he has received neither thanks, answer, nor recognition of any sort.

But I have not been idle, meantime, and if G. M. will read what I now have to say, he will see, and, I trust, accept the reasons for my lengthened silence. The reasons are two. I waited in hopes that some one would reply to his remarks, for here and there he has not quoted my words quite correctly; and I wanted to make further observations, by way of verifying my statements. Quod feci.

First of all, as regards the quotation from Mr. Darwin's book, it was not, of course, given word for word. It wasn't meant to be given word for word, and I thought that the absence of inverted commas would show as much, but I see now that my version is different in words and substance from the original. I am exceedingly obliged to G. M. for correcting me. I will be more careful in future.

I do not think, however, that my remark about the viscid drop, which exudes directly the rostellum is touched, is altogether wrong. At any rate there is no inaccuracy or confusion in what I said. A viscid drop does exude. I have seen it do so frequently. For instance, a viscid drop almost invariably exudes when the air is dry and the sun shining. Then, for some reason, the pollinia are not inclined to adhere, and bees, as if aware of this, scarcely deign to visit the spikes on fine days. I have fertilised literally scores of orchis flowers in Mr. Darwin's own way, i.e. with a pencil, and repeatedly a tiny drop of milky fluid has remained on the point of the pencil, without either pollinium becoming detached. Therefore please observe that I did not use the expression explosion, nor did I say a pollinia. By explosion, I presume, a forcible expulsion is intended. This will not apply to O. mascula. I have, also, on very many occasions, watched with great delight the drop

shoot out from the flower of Listera ovata and Neottia Nidus-Avis and once, while fertilising a spike of Spiranthes autumnalis, the flowers behaved in the same way, though not with such force. Besides, my statement is so easily proved or refuted. Let only anyone go out this lovely May day, and make the experiment with a spike of O. mascula, and, provided the sun is shining and the air dry, I believe a viscid drop will exude. For it must be remembered that a warm cloudy morning is necessary to enable the pollinia to escape freely, and indeed it is only on such a morning that I have ever seen humble-bees visiting the plant. Thus the chances of O. mascula being fertilised by humble-bees in the legitimate way are very often narrowed down to an extremely small margin.

themselves, concealed from view. For want of some name I will call this process the thong. This thong, then, is the wonder of the whole. While drawing it (May 1, 1882), I was entirely at a loss to account for its use, but subsequently it dawned on me. As far as I understand its economy at present, it seems to be attached at its upper end, something like the tongue of a frog, and, apparently, for the same reason. It is highly elastic and retractile. I do not observe that G. M. notices it. He says "should the pouch be depressed without the pollinia being removed, it rises and protects the viscid balls; or if

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Next, as to the lip or pouch which covers the viscid balls attached to the base of the pollinia. In the spring of 1882, I made this drawing of the anthers of O. mascula, and I think it is correct. I had it by me in 1883, when I wrote my paper, but I forebore from describing it, as I had already sent in too many diagrams, and there were the plates also in Mr. Darwin's book. I should like to make a few remarks about it now.

To my mind, and probably to the minds of those who examine the drawing attentively, the most wonderful part of this most wonderful piece of mechanism, is the central strap-like process arising from and attached to the rim of the pouch, and passing between the enclosed caudicles of the pollinia, until its end is on a level with the pollen-masses

Fig. 67.-Pollinium of Orchis mascula.

only one be removed, it rises and protects the other." Exactly so: but why? The pouch rises and returns to its place, I believe, because of this elastic thong, but not of its own accord. And further, I believe that this thong is expressly intended to prevent the removal of both pollinia at once, which it certainly often does do, for the humble-bee becomes quarrelsome when two pollinia are attached to his forehead, and tries to rub them off. This I have witnessed. One single pollinium, on the contrary, appears to cause little or no inconvenience. If this is a fact, it is a very interesting and marvellous one.

Then G. M. finds my description of the drying of the viscid disc rather misleading. Here is a drawing of a pollinium made on May 12, 1883. It is the most perfect one I have been able to observe

Notice the superb symmetry of its proportion, Notice particularly the viscid disc, and the way the caudicle is attached to it. Now, whether the viscid disc as a whole dries or not, seems to me a little beside the question. Perhaps it does, and perhaps it does not. I am not evading the question, but I prefer to ask how it would be possible to maintain such a structure as this pollinium perfectly rigid and in a perfectly upright position for 30 seconds even, without some depression taking place? How would it be possible even on an immovable basis? How would it be possible in architecture? Let us take an instance. A Greek column, the ideal of simplicity and strength, tapers towards the capital and thickens towards the base. The thickening occurs at onethird of the distance from the base, as being the weakest point. Experiment with a roll of moist clay. The construction, therefore, of this pollinium must evidently induce rather than prevent a subsidence, and the drying of the viscid disc can only assist in a secondary degree. What actually does occur during the operation of fertilisation is this. The humble-bee alights on the labellum and cranes his serviceable head well forward, in order to sweep the base of the nectary in a horizontal manner with his proboscis, so that when he withdraws his head, with a pollinium attached, the pollinium projects from his forehead, not at all in an upright position, but nearly at right angles. Why a forward movement of depression is bound to occur ! and even without the depression, the pollen-mass would strike on the stigma, only there would not be the same chance of leaving so much pollen. I trust this is plain now, but I trust also that G. M. will observe and consider for himself.

While touching on this subject, I wish to draw attention to another delightful piece of intentional adaptation. If, as I have just supposed, the thong retains the pouch in its proper position, then a mere forward thrusting movement on the part of the bee will not be sufficient to disengage the pollinia, a fact which I have often proved with the pencil; but a horizontal movement from side to side will be necessary, or a rotatory movement of the pencil, which amounts to the same thing. Now do please notice the shape of the nectary (SCIENCE-GOSSIP, April 1883, p. 76), widened as it is towards its end, like the mandibles of a spoonbill's beak, and do please tell me what it is for, if it is not to allow of the horizontal movement of the bee's proboscis? Perhaps you will object that the nectary is not widened throughout. I anticipated that objection on Aug. 22, 1884, by securing the proboscis of a dead bumblebee, and I found that it resembled a spear, with the shaft thickened at the base and tapering till it joined the head. The head was nearly inch long, and the shaft inch long (i.e. the head was of the whole length), and when compared with the length and shape of the nectary, the adaptation was so remark

able as to compel outspoken admiration. The nectary formed a case for the proboscis as if made to measure! Then, to assure myself of my theory, I took a fly-rod, and removing the top-joint, and holding the thicker end so as to give the remaining 9 ft. a gentle free horizontal motion, I observed the airy delineations and peculiar shape the rod took. Well, it was, of course, something like a flat paint-brush, the minimum of the sweep being at about 2 ft. 6 in. from the tip (i.e. of the whole, nearly). This was a most singularly faithful representation of the bee's proboscis, and the reason of the spear-like shape at once became apparent. Really this is worth close observance.

(To be continued.)

GOSSIP ON CURRENT TOPICS.

THE

By W. MATTIEU WILLIAMS, F.R.A.S., F.C.S. HE Editor of "The Popular Science Monthly" (New York) says "Harvard University is to be congratulated on its leadership in the important work of liberalising the traditional college education." This refers to a reform of the practice of forcing modern students, whatever their ultimate aim may be, to waste their time and degrade their intellects by the tedious and shallow cramming of memory with those dead languages which constitute the sole attainments of the dominating pedagogues, whose vested interests and monkish inheritance our universities are still constructed to uphold. The University of Harvard is a great and growing university, its degrees are justly honoured everywhere. What then will follow?

Simply the natural operation of the laws of supply and demand. A trip across the ocean is a trifling exploit now-a-days, and in itself an almost necessary element of a truly liberal education. Therefore, if Harvard continues moving in this direction faster than our universities the practical British parent, who is now groaning with disgust at the intolerable impediments that are placed on the threshold of our academies, will simply send his son where he can obtain what he requires; the useful and truly elevating culture of scientific education, without the preliminary penalty of learning what every sensible man contemptuously forgets, as soon as he enters upon the practical business of life. This competition will tell most powerfully on the non-clerical universities. Oxford and Cambridge will not for a long time be sensibly affected by it, but the London University and others which, like it, were intended by their founders to supply modern and secular requirements, may suffer seriously and soon. They will lose the students they can least afford to spare, viz. those endowed with the higher intellectual powers demanded by science, and who consequently

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