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Limnæa truncatula.

Var. albida is said to have

been taken in Surrey. At Bickley I have found a specimen with two broad whitish bands below the periphery. One of my largest specimens is from a small rivulet in Camden Park, Chislehurst, which is dried up for the greater part of the year. L. truncatula is fossil at Crayford.

Ancylus fluviatilis. In our district, at any rate, this shell varies little except in size, and the same may be said of A. lacustris. The latter species, however, is occasionally compressed at the sides.

T. D. A. COCKERELL. (To be continued.)

reaching description, his vigilance is indefatigable, and let but pressing danger be apprehended, and lo! he dives beneath the water with marvellous promptitude and dexterity. Where is the sea-fowler that can overmatch the astuteness and agility of this beautiful bird? The gun is presented, and well and truly pointed; the trigger is pulled, but ere the comparatively sluggish shot can reach its mark, the creature has vanished-disappeared, as if by magic, to nestle in the chambers of the deep, completely out of sight and in security.

During the dry and parching summer season, the red-breasted merganser (for that is the name of this

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Fig. 125.-Red-breasted Merganser (Mergus Merganser), Yarrell. (The larger bird after Morris.)

THE RED-BREASTED MERGANSER.

By P. Q. KEEGAN, LL.D.

BOUT the period of the autumnal equinox, at

the time when the winds, let loose from their summer-caves, sweep with wild and fitful fury over land and sea, then away among the quiet, retired recesses of some sheltered bay, there may frequently be discerned a most beauteous sea-bird. Arrayed in an apparel of the most gaudy and varied hues, with neck and head and movement correspondingly beautiful and graceful, the appearance and deportment of this bird may challenge universal admiration. His accomplishments, too, are by no means to be despised. His sight is of the sharpest, most far

beauteous sea-bird) sojourns for the most part amid the desolate solitudes of the Arctic regions. The cares and anxieties attendant upon the breeding duties harass him then; but let no one suppose that, at this time, his lot is unhappy and difficult to bear. Let no one think that there he encounters no warmth or geniality of climate, no green vegetation, no sunlit skies or gleaming sea. We know that there is a broad space around the pole-a "thrilling region of thick ribbed ice" where, during certain months in summer, the sun perpetually shines, his light never fades, never gives way to night, though sometimes it is seriously intercepted by fog, which, however, chiefly occurs seaward; he careers all day and night in the heavens, and thereby concentrates such an

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intensity of heat upon certain sheltered portions of the land, that the temperature thereof frequently surpasses that of the tropics. Captain Scoresby during the course of his survey of the eastern coast of Greenland, having landed one day on that desolate shore, found the temperature of a certain spot amongst the rocks to be 70°, and he describes the effect thereof as being particularly relaxing. lavish and widespread vegetation too, decorates these northern shores from June till about September, and furnishes ample opportunity for the prosecution of breeding undertakings on the part of sea-birds. In order, however, to illustrate the fact, that birds can nidify at a comparatively low temperature, we may mention, that, on the 21st of June, 1853, an ivory gull (Larus eburneus) was found sitting upon its eggs in a small island to the north of Melville Sound (lat. 76°), when the thermometer indicated only 35° of heat.

As soon as the breeding duties of our bird have terminated, and the new-fledged brood can provide for themselves, and when the terrible rigours of the Arctic winter-the sleet-charged blasts, the blighting fogs, the destruction of vegetation, the souldepressing silence and frigidity of all things-commence to be experienced, then he abandons his summer seat, and travelling southwards, settles in more genial latitudes. With strong, rapid unflagging flight, he poises in the air over the dreary shores of Greenland, Newfoundland, or Hudson's Bay, and bidding them farewell, advances briskly for days and days till he lands securely in Shetland, in Orkney, in Sutherland, or the Hebrides, &c., and there, in conjunction with his "co-mates and brothers in exile," forthwith commences his winter campaign of diving, fishing, glutting, &c.

Unlike the great black-backed gull, the beauteous northern diver, the Fulmar petrel, &c., the bird now under review is of a decidedly social disposition, and, on that account, is more frequently to be seen in flocks than in a solitary state. Its voracity is excessive and generally known; and we need not wonder, therefore, that its principal occupation consists in the pursuit, capture and consumption of various species of fish, especially sand-eels, for which it manifests an especial relish. The following is the method of procedure.

The bird swims about gracefully upon the surface of the sea for some little time, occasionally poking its head and neck beneath the water, as if searching about for some delicate morsel, then, suddenly elevating its body, and plunging straight ahead, it instantly disappears from view. Its comrades, suspecting that some sport is to be had below, follow suit; so that the entire flock seems to vanish, as if by magic. After traversing the watery regions with considerable swiftness and dexterity (using the wings as well as the webbed feet), the merganser appears once more above the surface, bearing a fish in its

mouth, and looking as lively as ever. The booty is soon disposed of down "red lane," whereupon the bird drinks a little water by way of condiment or digestive, or perhaps to wash the meal down more thoroughly; and then gleefully flapping its wings, it appears eminently satisfied with the entire proceeding. To inspect a pair or more of these birds fishing in some shallow lake left amid some far off waste of sand by the receded tide, is an extremely interesting occupation. Such graceful movements, such displays of agility, such attractive forms and colouring cannot be discerned every day within the circle of human intercourse. He who, towards the autumn or mid-winter, occasionally devotes an hour or so to the study and contemplation of sea-bird habits and deportment, will assuredly not repent of the proceeding. The ever-varied and beautiful tints and shades of ocean, the bleakness and desolation of open wastes of beach-sand, will touch his heart, and impress grateful ideas on his mind that will haunt him for years.

The lavish prodigality of life-energy expended by the red-breasted merganser, the pungent stimulating character of the regions which it inhabits during the most important period of its existence, conspire with extensively endowed digestive powers to render it excessively voracious. The mouth is provided with a number of fine, conical, saw-like lamellæ or teeth, viz. about sixty in the upper jaw and about thirty-five in the lower. The oesophagus also is specially large and dilatable, so that ample provision is thus wise made for the capture, steadfast seizure, and the storing up of a liberal amount of edible matter. Sand eels are especially delectable to the gustatory organs of the bird. Away upon a desolate waste of sandy shore, damp, pool-bespread, and wreck-strewn, the bird establishes itself, and commences the operations necessary to the procurement of victuals. It perseveringly digs its sharp beak into the retreats of the sand-eel, until a desiderated morsel is grasped. This species of eei is of a beautiful silvery colour-a very delicate fish about five or six inches long; so that the merganser in whose body it is recorded no fewer than twenty-four of these were found, had managed, we should say, to obtain a pretty good dinner of it!

Hovering on the confines of the comparatively clumsy Anatidæ, the mergansers seem to have borrowed some portion of their marvellous beauty and gracefulness from the allied family of the Colymbidæ. The diving powers of our bird are remarkable. It is shy and wary, with sharp ears, and exceedingly acute and far-ranging vision, and so completely, so adequately and promptly can its bodily movements be adjusted to the dictates or promptings furnished by the senses—so intimately associated and dependent are its motor and sensor nerves that when a sea-fowler fires off his gun, the bird dives with incredible dexterity, disappearing from

view ere the shot can reach the now deserted seat. The predilection of the bird for red colour, however, is the snare which frequently proves fatal. It is recorded, that this merganser exhibits a weakness for the fascinations of this colour, and that the Swedish hunters, aware of this fact, frequently take advantage of it, and by wearing red clothes become enabled to approach much nearer, so as to direct their fire with more sure and deadly effect.

The wings of the red-breasted merganser are only of moderate length (not extending to the tail),—and of moderate breadth. The body, like that of the divers (Colymbidae), 'is comparatively heavy, weighing in an ordinary specimen about two pounds. Yet, notwithstanding the unfavourable circumstance, the flight of the bird is undoubtedly strong, swift, and remarkably well sustained.

thorough-bred horse, or even (if such be allowed) with the locks of the well-bred gentleman, and then declare if, as respects this important constituent of their external aspect, they are not entitled "to flourish in any society." To speculate upon the social position or upon the respectable appearance of birds, may appear ridiculous; but my observations and studies in Natural History have been wholly valueless, if roughness or smoothness, coarseness or refinement in the external integuments, in the hair, nails and other appendages of animals, does not stand as a sign and index, a mark and register of something more recondite and fundamental, of something intimately connected with the most elementary organic structures, and with the ultimate fountains of animal energy.

Every movement of these mergansers is preeminently graceful. The stream of their animal energy flows easily and readily, and through as it were a smooth and well-worn channel. The bonejoints seem perpetually well-oiled and competent, and the muscular apparatus is thoroughly sound and destitute of deteriorating fatty admixture. The instruments of bodily movement being thus wise constructed of sound and unexceptionable materials, and being admirably adapted to the end for which they were proposed, the utmost ease and harmony of movement may be expected. To endeavour to furnish an explanation of the admirable quality of gracefulness exhibited by animals, would be a supremely interesting undertaking; but it is one from which the restricted limits of our space warn us to desist. We have no doubt, however, that this. quality depends entirely upon (1) hereditary endowment, and (2) the manner in which, during youth and early life, the various bodily movements have been conducted, and the consequent change and modelling as it were of the organism in accordance therewith.

Now if we compare these facts with those furnished by an inspection of the flying apparatus, of, say the great black-backed gull (Larus marinus), we shall perhaps be able to glean some grains of ornithological truth. Have you ever observed the mighty sweep of this gull's wings? They measure five feet across, and the weight of the bird itself is, on the average, only about three or four pounds. Now, if we compare these various weights and measures with those of the body and wings of the red-breasted merganser, the important truth may flash upon us, that the greater the weight of a bird, the less proportionally is the spread of the wing necessary to sustain its body in the air. In the consideration of the flying capabilities of a bird, let us never forget the fact, that, in heavy birds, the motion of the wings in the act of flying is comparatively slow, while in light birds, it is comparatively swift. The former circumstance is illustrated in the dilatory, lazy-paced, ungainly flying of the crane, the heron, &c., the latter in the marvellous agility of wing displayed by the sylph-like petrels, skuas, terns, &c. It seems, too, to be an indisputable fact, that the larger and weightier birds, when once fairly launched into the air, can sustain and propel themselves with a much less expenditure of animal energy than that required from the smaller and less ponderous among the feathered tribes. Those naturalists who have marvelled at the apparently excessive muscular exertion involved in the flight of birds, have, when the facts have been more thoroughly examined and elucidated,│spicuous and important peculiarities of colouring, &c.,

become sensible that the strength of these aerial creatures is not so grievously taxed as they formerly supposed.

The red-breasted merganser, ever beautiful and accomplished, and not exhibiting any very marked or reprehensible meddling, domineering, piratical or other objectionable proclivities, may be fairly ranged as regards "social position" on the same level with the "aristocratic" divers. Inspect and feel the soft, close, blended, velvety plumage of this latter group of sea birds, and compare it with the hair of the

The hand of Nature has been employed so assiduously in the lavish decoration of the sea-birds under review, now touching with red and green, now patching and interlaying with yellow, white and black, now dropping spots of black and grey, and shreds of scarlet, and polishing all into soft and uniform lustre, that fain would we be excused from recounting the specific delineation thereof. We must rest content, therefore, with a notice of the more con

as exhibited by the male bird during the breeding season. We know not how it comes to pass that among many tribes of the lower animals, the male is much handsomer, more attractive in appearance, more gaudily attired, than the female. Perhaps the lady in this case is more coy, or more fastidious in the selection of a mate; or mayhap the superior attraction of the males of her own species may counteract any inclination on her part to extend favours to individuals not holding precisely the same position as to organisation, &c., in the animal world.

The following account of the specific characteristics of the male red-breasted merganser (Mergus serrator) cannct be regarded as complete :-The head is decorated with a long loose crest of a glossy dark-green colour; the upper mandible is reddishbrown, the lower one is of an orange tint; a few rather large feathers, of a pure white colour margined with black, crop out from each side of the breast, and fold over the wings when these are at rest; the upper breast is reddish-brown, the lower is pure white, but when the bird is just recently killed, there is thereabouts a beautiful salmon-colour tint; the outside of the tarsus and toes, and the webs are of a purplish shade, while the claws are of a light greyishbrown. The total length of the bird is about twentyone inches. As is the case with almost all the Anatidæ, a most important specific indication is afforded by the appearance of the trachea. In the red-breasted merganser, the structure and arrangement of this organ are so singular as to merit a detailed description. Two inches from the mouth, it swells out to four times its diameter, an enlargement which it maintains for the space of two inches and a half; it then continues as at first for another couple of inches, when it becomes flattened for the same distance further; it finally appears under the form of a bony labyrinth which measures two inches long, by one and a half in breadth, and which is covered with a yellowish skin-like parchment.

This species nidifies from about March till May or June. Greenland, Newfoundland, and the shores of Hudson's Bay are the localities which have been notified as its special haunts during the breeding season. But away along the margins and among the islands of the more lonely and secluded Highland lochs, the nest of this bird has been frequently discovered. It is said to be commonly situated amongst brushwood, and at a few yards from the water, and to be warmly constructed with the down taken from the bird's own body.

The persecution to which this beautiful bird has been subjected by the human race for ages past, may be inferred and estimated from the contemplation of its incomparable diving powers, and by its shyness and general deportment when pursued. The love of power inherent in man, which, in the destitution of ether means of gratification, seeks to slaughter the beasts of the field and the birds of the air, has been especially directed against this beautiful merganser. We cannot here enter into a discussion regarding the relation which may subsist between the shyness and vigilance of the bird, and the amount or kind of persecution to which it has been subjected, since the unlucky period when it first became known to human beings. Nor can we venture to suggest a cause or reason for the gorgeous apparel with which it has been clothed. Neither can we confidently pronounce whether this ostentatious drapery subserves any particular purpose, whether it exists only to please

the eye of man, or whether the bird is beautiful for the mere sake of beauty. All these questions are replete with interest, and furnish ample material for the reflective and thoughtful mind; but, at the same time, they are fraught with danger. They contain many mazes and labyrinths, which are difficult if not impossible to thread, and which are ever liable to land the rash and unwary speculator in quagmires and obscure haunts, where the glorious light of religion is for ever quenched. Perhaps the most unequivocal mark of design, connected with the subject of our paper, is the peculiar structure of the beak. Unlike that of the generality of the duck family, it is adapted, not so much for straining the water and the sandy particles from the edible morsel within the mouth, as to effectually seize and firmly retain the solid body of a fish.

PELORIC FORM OF ORCHIS MASCULA.

PEL

ELORIA, or the regular form of flowers normally irregular, seems to be most common among flowers with spurred petals. In Linaria, with one spur, the flowers are sometimes altered so that all the petals are spurred. In Columbine, on the other hand, with all the petals spurred in their normal condition, forms are sometimes found with the spurs suppressed. For peloric forms to be found among the orchids is, however, much less common. We have, growing wild, in this neighbourhood, about three plants which every year produce these curious forms. I first found them last year, and sent specimens to two or three friends, who, like myself, were much puzzled, and could make nothing of them. One gave it up in despair, another thought the plant might be Epipactis purpurea, but could not make form of ovary to agree. This year I submitted specimens to Dr. Hooker, who was much interested with them, said he had seen nothing like them, and pronounced them to be peloric forms of O. morio or mascula. After subsequent examination and information he decided upon mascula. I regret I have not a specimen to send for engraving, and my description, from memory, must necessarily be vague. I hope, however, to remedy these defects next year. The most striking difference is in the form of the lowest petal, which, instead of being much larger than the upper pair, and spurred, is equal in size and form to the other two, and without the spur. The petals of the upper pair are larger than in ordinary forms of the flower; all are purple and without spots. The calyx is coloured like the corolla, the three sepals are about the usual size; so that the floral leaves, six in number, are alike in colour and size, and the perianth is therefore regular. As there is no spur, and therefore no apparent receptacle for honey, it seems difficult to understand how this form can be reproduced. A friend of mine informs me on the authority

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"What do you feed them on?" "How often do you change the water, and where do you get your supply of fresh water from?" Such are the questions we have answered repeatedly since we began to keep anemones, and as our efforts have been attended with much success, we venture to think a record of our experiences may be acceptable to many readers of SCIENCE-Gossip.

One fine afternoon, towards the close of our stay at Beaumaris, in July 1883, we went down on to the beach just as the tide reached its lowest ebb, bent on anemone collecting. Our outfit consisted of a fishcan and a pocket knife. The hammer and chisel recommended in the books were left behind, being unnecessary and burdensome.

We had not proceeded far before we came upon several specimens of the common daisy anemone (Sagartia bellis), and as we had determined that this species should be the subject of our first experiments, we very carefully detached them with the blade of our pocket knife from the large pebbles to which they adhered, and transferred them to a small quantity of clean sea-water in our fish-can. In less than an hour we had collected more than sufficient for our purpose, so we examined our captures, and, after selecting six of the largest and healthiest-looking, we put the rest back into the sea. "Have you been exploring a bit?" said a lady to us as we neared the pier. Our explanation of the purpose of our exploration brought a look to our friend's face that spoke volumes. What attraction" nasty lumps of jelly" could have to young men like us seemed a mystery, and we were going to take them all the way to Manchester too! On the following morning we hired a boat, and taking with us a gallon glass jar and some smaller bottles, we rowed into mid-channel. Here we filled our jar and bottles with sea-water and collected a quantity of floating sea-weed in which to pack our anemones, an operation which we performed just before leaving Beaumaris for home in the afternoon. A layer of wet sea-weed was put at the bottom of the fish-can, the anemones laid upon it, and covered with another layer of the same.

Upon our arrival at home we inverted two propa

gating glasses, each about twelve inches in diameter, fixing one in a turned wood stand, the other in a bed of saw-dust contained in a glass sugar basin. Into each glass we put a quantity of well-washed gravel and two or three fragments of limestone, and after pouring in the whole of our sea-water, we transferred our anemones to their new home, putting three into each glass. Our efforts were soon rewarded. Tentacles were protruded, and after sundry peregrinations round their glasses, the daisies settled down into the positions which they occupy to-day. But imagine our dismay when, a day or two later, we saw that the water had assumed a milky hue.

We thought we were doomed to disappointment, especially as the milkiness seemed to increase. But seeing that the anemones were fully expanded, and apparently unmoved by the threatening state of things, we took a glass syringe and with it vigorously syringed the water. This had the desired effect. The cloudiness soon disappeared, but we continued to syringe the water almost daily for some time, and still do so occasionally.

Our next care was to provide the anemones with suitable food. We bought some mussels, and with a knife cut several of them in half. We then removed the leaf-like gills with a pair of scissors, and after cutting them into small pieces, gave a morsel to each with a pair of wooden forceps. The jack-in-the-box-like celerity with which the tentacles closed over the food, and its speedy disappearance into the digestive cavity showed that it was appreciated, and the completion of the process of digestion was duly announced on the following day by the ejection through the mouth of rounded pellets composed of the innutritious residue. These were carefully removed with a pipette. Feeding time has since recurred at intervals of three weeks or a month. One morning early in the following month we noticed on the disk of one of the daisies a small pearly-white body. What was it? A young one, sure enough. The next day saw the infant fixed on a small pebble, beginning life on its own account. Another and another soon followed, and by the end of the year about twenty had made their appearance.

But the rate of increase in July and August last year astonished us. Three adults, during those two months, gave birth to at least seventy young ones, about forty of which we distributed at a subsequent meeting of the Manchester Microscopical Society. During the earlier months of the summer we had frequent opportunities of observing the very young larvæ. They are small, somewhat pear-shaped, ciliated planulæ, the pointed anterior pole of which carries a tuft of longer cilia, the opposite end somewhat flattened, bearing the mouth in its centre. They swim freely with a peculiar oscillatory move

ment.

The hot weather during the above-mentioned months seemed to promote the growth of a filamen

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