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three specimens were inclosed in a single lump of hard mud, weighing when dry about. twenty pounds.

One of the cocoons is now lying before me, together with the dried and shrivelled body of its former inhabitant, still curled up in the singular fashion already mentioned. The walls of the cocoon are composed of a thick greyish clay, quite hard and dry, and intermixed here and there with remnants of vegetable matter. The hollow in which the Lepidosiren resided is quite smooth in the interior, but gives no idea of the real shape of the inhabitant, the cell seeming to be somewhat large, most probably on account of the coat of mucous substance with which it was lined, and part of which is to be seen still adhering, like flakes of dry membrane, to the sides of the cell.

By rapidly tearing this membranous substance with an oblique bearing, it can be in some places split like a scrap of paper under similar circumstances, but when placed under the microscope, it shows no signs of organization, being of a light brown colour, irregularly mottled with black. When burned, it rapidly takes fire and bursts into flame, giving out a very nauseous odour, like that which is perceived on burning the wing-case of a beetle, and leaves a firm black ash, of nearly the same shape and form as before the light was applied to it.

The remainder of this substance is found loosely adhering to the body of the former inhabitant, and can be easily stripped off.

On being immersed in water, the earthy cocoons fell to pieces as if they had been made of sugar, and the imprisoned creatures were thus released. At first they were exceedingly sluggish, and hardly stirred, but after the lapse of an hour or two they became tolerably alert.

One of these specimens died after it had been kept about six weeks, and a good plastercast of it is now before me. Its length is ten inches, and the circumference of the head, just in front of the fore pair of limbs, is exactly three inches. The scales are tolerably well marked, and are shown even in the plaster-cast, though in the living animal there is hardly a trace of them. They are also very evident after the creature has been immersed in spirits for some time. In taking a cast of the Lepidosiren, the mucous secretion with which the body is covered affords a serious obstacle to the correctness of the image, as it is apt to adhere to the plaster, and pull away with it some portions of the skin. A fellow-specimen, that floated dead from its cocoon, is also before me, bent on itself in the manner usual among these creatures, and with its mouth widely open, showing the peculiar teeth.

Finding, as has already been mentioned, that the Lepidosiren would rise to the surface of the water when a splashing was made, the attendants used to feed it by paddling about with the finger, and then holding a piece of raw beef in the spot where the disturbance had been made. The creature used to rise deliberately, snatch the meat away, and, with a peculiarly graceful turn of the body, descend to its former resting-place for the purpose of eating its food.

The mode of eating was very remarkable. Taking the extreme tip of the meat between its sharp and strongly formed teeth, it would bite very severely, the whole of the head seeming to participate in the movement, just as the temporal muscles of the human face move when we bite anything hard or tough. It then seemed to suck the meat a very little farther into its mouth and gave another bite, proceeding in this fashion until it had subjected the entire morsel to the same treatment. It then suddenly shot out the meat, caught it as before by the tip, and repeated the same process. After a third such manœuvre it swallowed the morsel with a quick jerk. The animal always went through this curious series of operations, never swallowing the meat until after the third time of masticating.

After a while, it was thought that the water in which it lived was not sufficiently warm to represent the tepid streams of its native land, and its tank was consequently sunk in the north basin of the building, where the water is kept at a tepid heat for the purpose of nourishing the tropical plants which grow in it. Here the creature remained for some time, but at last contrived to wriggle itself over the side of its tank, and roam about in the large basin quite at liberty.

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FOOD OF THE LEPIDOSIREN.

It remained here for some time, and being deprived of its ordinary supply of raw beef, took to foraging for itself. The gold-fish with which the basin is stocked became its victims, and it was quite as destructive as an otter would have been. It had quite a fancy for attacking the largest fish; and though apparently slow in its movements, could catch any fish on which it had set its wishes. As the fish was quietly swimming about, suspecting no evil, the Lepidosiren would rise very quietly beneath it until quite close to its victim, just as the terrible ground-shark rises to take its prey. It then made a quick dart with open mouth, seized the luckless fish just by the pectoral fins, and with a single effort bit entirely through skin, scales, flesh, and bone, taking out a piece exactly the shape of its mouth, and then sinking to the bed of the basin with its plunder. The poor fish was never chased, but was suffered to float about in a half-dead state. and numbers of mutilated gold-fish were taken out of the basin.

I have several times seen the creature while swimming about in search of a dinner, and have been much struck with the exceeding grace of its movements, which indeed very strongly resemble those of the otter.

At last its depredations were checked, for when the basin was cleansed, according to custom, a portion was fenced off, so that the Lepidosiren could not get out, and the goldfish could not get in.

Not choosing to supply a succession of gold-fish, out of each of which the fastidious creature would only take one bite, the superintendent bethought himself of frogs, and fed the animal regularly with these batrachians. But having been warned, by the effects on the gold-fish, not to trust his fingers within reach of the teeth that could inflict such very effective bites, he got a long stick, cleft one end of it, put one hind-foot of the frog into the cleft, and held it on the surface of the water, so that the struggles of the intended victim should agitate the surface, and warn the Lepidosiren that its dinner was ready. No sooner did the frog begin to splash, than the Lepidosiren rose rapidly beneath it, seized it in its mouth, dragged it off the stick like a pike striking at a roach, and sunk to the bottom with its prey. Not a vestige of the frog was ever seen afterwards; and Mr. Wilson naturally conjectures that the poor victim was gradually chewed up, like the beef with which the creature was formerly fed.

Under this regimen the Lepidosiren grew apace, and in three years had increased from ten inches in length and a few ounces in weight, to thirty inches long, and weighing six pounds and a quarter. The rapidity of its growth may be accounted for by the fact, that it had fed throughout the entire year, instead of lying dormant for want of water during half its existence, and its size was apparently larger than it would be likely to attain in its native state.

Thinking that perhaps the creature might need its accustomed season of reposehappily called æstivation, in opposition to the term hibernation-it was well supplied with clay similar to that from which its cocoon had been formed, but without any result, the animal evincing no disposition to avail itself of the stores so thoughtfully collected in its behalf. This is, I think, a very interesting example of the manner in which nature accommodates herself to circumstances, and is paralleled by many other instances in the several departments of Natural History. Bees, for example, on finding themselves within easy distance of a sugar plantation, have been known to decline honey making; and the same result has occurred when they were transported to fertile localities where the honeybearing flowers are in blossom throughout the year.

As an example of a similar phenomenon occurring in the vegetable kingdom, I may instance some Australian flowers brought over by Mr. Howitt, and planted in his garden in the suburbs of London. These plants were at first sadly puzzled by the seasons, wanting to blossom just as our winter had set in, but in the course of a few years they grew gradually later in blossoming, until they had found the proper season, and then were content to put forth their leaves and flowers at the same time as the indigenous plants.

The cause of this specimen's regretted death was rather curious. In the winter time, when the basins were cleaned, the animal was removed from the north to the south basin while the former was being emptied. Unfortunately, the fires which warmed the water

SKULL OF LEPIDOSIREN.

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were suffered to expire during the night, and in the morning the poor Lepidosiren was found chilled to death.

The history of this creature is not only interesting, but is valuable as it shows the comparative advantages of watching the habits of animals in large and small habitations. Had, for example, the creature lived from the first in the large basin, its remarkable mode of eating its food could not have been observed, as it always seeks the bottom of its prison for that purpose; while, had it been always kept in the glass tank, its graceful movements and fish-eating propensities would never have been discovered.

The bones of the Lepidosiren are, when first taken from the body, of a bright green colour, and so gelatinous in structure, that if left in the water they would probably dissolve. After a time, however, the green colour fades, though traces of it can still be discerned. The bones of the head are, however, of a firmer character, as is needful for the management of the sharp and powerful teeth; and in the skull of the abovementioned specimen, now lying before me, and from which this illustration has been carefully drawn, the green tint still lingers on several of the bones. The drawing is of the natural size.

The teeth are most remarkable, looking as if they were made from a ribbon of enamelcovered bone, plaited in a series of very deep undulations in front, and sweeping off at each side with a bold curve. Those of the palate and lower jaw are so made that they lock into each other, the folds exactly corresponding, and fitting into each other with such exactness, that no creature when seized could hope to escape without much detriment. The edges of this continuous tooth-ribbon, if I may so call it, are very sharp, and armed with small saw-like teeth, rather worn away in front, but very perceptible on the sides. In the very front of the upper jaw are two little pointed teeth, set apparently loosely in the soft parts of the nose, and quite useless for biting. When, however, the skull is removed from the body, and cleared of muscle and other soft parts, these teeth retain their place, and by the hardening of their attachments become tightly fixed in the skull.

During life the points of these teeth project very slightly through those two little holes just inside the upper lip, which are considered as the internal nostrils. While the creature is alive, the teeth cannot be seen even when the mouth is open, being covered by a very soft and yielding substance, through which they seem to cut when in use.

The external aspect of this creature is very singular, the chief characteristics being its eel-like form, and the four long slender projections which stand in the place of limbs, and

are analogous to similar structures in certain reptiles already described and figured. These are not true limbs, and the cartilaginous ray by which they are supported has no joint. They are quite soft and flexible, as if they were made of leather, and are of very trifling use in locomotion. The two fore-limbs are set at the shoulders, just behind the head, and widely separated from each other, while the hinder pair are quite close together at their bases. In the species just described, two short tubercular appendages, about an inch in length, accompany the larger limb-like projections, and, except in dimensions, bear a close resemblance to those organs. I may take this opportunity of remarking that the creature is not known to leave the water and to crawl on land, and that the figure is represented as lying partly on the bank of the stream, not to intimate that it is capable of terrestrial locomotion, but merely in order to show the peculiar shape to better advantage.

The specimen now (January, 1862) living in the Zoological Gardens has not attained to any great size, being scarcely half as large as the individual just described, though it has lived in England for three years. The tank in which it resides is small, and may probably account for the slight increase in dimensions. It is interesting to watch this creature move about its prison, as the peculiar screw-like or spiral movement of the limbs is well exhibited.

The whole body is covered with rather large scales, embedded deeply in the skin, and not easily to be seen in living specimens. The name of Lepidosiren, or Scaly Siren, is given to this creature on account of its scaly covering. At about one-third of the distance from the head to the tip of the tail a rather narrow and fin-like membrane arises, which runs completely round the tail until it is terminated close to the bases of the hind pair of limbs. It is strengthened throughout by a series of soft jointed rays.

The flesh of the Lepidosiren is very soft and white, and is thought to be excellent for the table, so that in its native country it is dug up from its muddy bed and used for food. It usually burrows to a depth of eighteen inches. This creature possesses both lungs and gills, the latter organs being twofold, the external gills being tufted on the under side, and the internal gills being placed on the edge of the divisions between the gill openings on the side of the neck. The heart is more reptilian than piscine, having three compartments, two auricles and one ventricle, and affords one of the strongest reasons for ranking the creature among the former class.

There are several species of Lepidosiren, divided, in the catalogue in the British Museum, into two genera, distinguished from each other by the number of ribs. The species which is found in Southern America, and is there known under the popular name of CARAMURU (Lepidosíren paradoxa), has fifty-five pairs of ribs, whereas the African species has only thirty-six pairs. The colour of the Lepidosiren is darkish brown with a wash of grey.

THE next order of Crawling Batrachians is called by the name of Meantia, and contains a very few but very remarkable species. In all these creatures the body is long and smooth, without scales, and the gills are very conspicuous, retaining their position throughout the life of the animal. There are always two or four limbs, furnished with toes, but these members are very weak, and indeed rudimentary, and both the palate and the lower jaw are toothed.

The first example of this order is the celebrated PROTEUS, discovered by the Baron de Zois, in the extraordinary locality in which it dwells.

At Adelsberg, in the duchy of Carniola, is a most wonderful cavern, called the Grotto of the Maddalena, extending many hundred feet below the surface of the earth, and consequently buried in the profoundest darkness. In this cavern exists a little lake, roofed with stalactites, surrounded with masses of rock, and floored with a bed of soft mud, upon which the Proteus may be seen crawling uneasily, as if endeavouring to avoid the unwelcome light by which its presence is known. These creatures are not always to be found in the lake, though after heavy rains they are tolerably abundant, and the road by which they gain admission is at present a mystery.

The theory of Sir H. Davy is, that their natural residence is a deep subterraneous

lake, from which in great floods they are sometimes forced through the crevices of the rocks into the places where they are found; and it does not appear to me impossible, when the peculiar nature of the country is considered, that the same great cavity may furnish the individuals which have been found at Adelsberg and at Sittich."

Whatever may be the solution of the problem, the discovery of this animal is extremely valuable, not only as an aid to the science of comparative anatomy, but as affording another instance of the strange and wondrous forms of animal life which still survive in hidden and unsuspected nooks of the earth.

Many of these animals have been brought in a living state to this country, and have survived for a considerable time when their owners have taken pains to accommodate their condition as nearly as possible to that of their native waters. I have had many opportunities of seeing some fine specimens, brought by Dr. Lionel Beale from the cave at Adelsberg. They could hardly be said to have any habits, and their only custom seemed to be the systematic avoidance of light. Dr. Beale has kindly forwarded to me the following account of these curious creatures :

"One of the Proteuses I brought over from Adelsberg lived for five years, and, what is very interesting, passed four years of his life in the same water, a little fresh being added from time to time to make up for the loss by evaporation. He lived in about a quart of water, which was placed in a large globe, this being kept dark by an outer covering of green baize. Perhaps half a pint of water may have been added during two years.

He was not once fed while he was in confinement, and one of his companions died soon after taking a worm before he had been two years in this country.

The one I kept was very active, and his movements were as rapid as those of an eel. He was thinner just before death than when he was brought from the cave, but the loss of substance was so very slow as not to be perceptible from year to year, and to the last he retained the power of performing very active muscular movements.

His external gills always contracted when a strong light was thrown upon them. The circulation of the blood in the vessels of these organs was very often exhibited; the animal being placed in a long tube with a flat extremity, provided with an arrangement for the constant supply of water, and on several occasions some of the large blood corpuscules were removed for the purpose of microscopical examination, so that the animal was not placed under the most favourable circumstances for living without food. There are probably very few more striking examples of very slow death from starvation than this, and it is probable that the ultimately fatal results were as much caused by