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LIGN. 112.-SKELETON OF THE MEGATHERIUM CUVIERI (AMERICANUM).

(Height, 8 feet; length, 12 feet.)

right arm clasping a tree, is of course hypothetical; and the position of the hinder toes and feet does not appear to be natural; altogether, however, the construction is highly satisfactory, and a better idea of the colossal proportions of the original is conveyed by this model, than could otherwise have been obtained. The skull of this creature is short and truncated, and the zygomatic bone sends off a large descending apophysis which is a remarkable peculiarity. The molar teeth, of which there are five on each side the upper jaw, and four in the lower, are hollow prismatic cylinders, straight, and from seven to nine inches long, and implanted the greater part of their length in deep sockets; there are no other teeth, and the crowns of the molars are so constructed as always to present two cutting, cuneiform, salient angles, in consequence of the mutual adaptation of the corresponding surfaces of the upper and lower series. The feet are nearly equal; the entire fore-foot is about a yard in length. The outer toes are destitute of nails, the others have unequal phalanges, the median being the longest and largest. The pelvis is of enormous dimensions, and very solid; the iliac bones are at right angles with the spine, and extremely rugous; their margins form two projecting branches, measuring 4 feet across, a dimension exceeding that of the same parts in any living terrestrial mammalian.

The most remarkable character of this portion of the skeleton is that the cotyloid cavity is directed entirely downwards, so that the femur supports the body without any obliquity; a structure that must have contributed to the solidity and strength of the hinder part of the body. The femur is three times as thick as that of the largest Elephant, and its length scarcely twice that of the breadth. The tail is very thick and strong; there is a fine series of caudal vertebræ in Upright-Case 4.

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LIGN. 113.-RESTORED OUTLINE OF THE MEGATHERIUM GIGANTEUM.
(The original 12 feet in length.)

From the osteological characters thus cursorily noticed, it is obvious that the Megatherium was a bulky and powerful creature, presenting in its general form the outline given in Lign. 113. The structure of the teeth is analogous to that of the Sloths, and indicates the food of the

original to have consisted of plants and leaves or the young branches of trees. My friend Sir Woodbine Parish, whose long residence in South America enabled his active and sagacious mind thoroughly to investigate the phenomena connected with the ancient fauna of that country, has solved the problem as to the source whence the Megatheria and allied herbivorous animals could have derived support, by pointing out the Agave or American Aloe, as yielding an ample supply of food, and of a kind, for the comminution of which the teeth of the colossal edentata appear to have been specially adapted.

MYLODON. Of this genus, which is closely allied to the Megatherium, there are bones, teeth, and jaws from South America, in Room II., ante, p. 77.1

With the huge animals above described, were associated those not less gigantic in relation to their modern prototypes, the Glyptodon, (ante, p. 359,) and the Chlamydotherium, which were covered by a tesselated osseous cuirass, like the existing Armadillos of the present day. SCELIDOTHERIUM. - The animals of this genus are allied to the Megatherium. Mr. Darwin obtained an almost entire skeleton of the S. leptocephalum; the original must have been as large as a Rhinoceros. Four species have been discovered; there are some fine bones of two or three species from the caves of Brazil, in Wall-case C.

Such were the gigantic mammalia that inhabited the dry land of South America at a comparatively recent period; and it is worthy of especial consideration, that though these types have been long extinct, Sloths, Ant-eaters, and Armadillos, are still the characteristic mammalia of that country, and these diminutive forms are the only living representatives of the colossal Edentata of the ancient world.

CHAPTER VI.-PART VI.

FOSSIL MAMMALIA OF THE CAVERNS.

OSSIFEROUS CAVES OF THE BRAZILS.-Wall-case C.-The fossil remains in this cabinet were obtained by Dr. Lund and M. Claussen, from certain limestone caverns in the Brazils, which, like those of Europe, abound in bones of mammalia, imbedded in a reddish coloured loam, and more or less incrusted with stalagmite. The animals belong for the most part to genera still inhabiting the American Continent, intermingled with the extinct types of some of the Edentata,

1 See "Wonders of Geology," p. 168. A splendid skeleton of this animal is preserved in the Hunterian Museum, and is described and illus trated in a "Memoir on the Mylodon robustus, by Professor Owen;" published by the Royal College of Surgeons.

of which we have already spoken; as, for example, the Scelidotherium, Glyptodon, Clamydotherium, &c.; of these there are many perfect bones, and portions of the dermal cuirass of the two latter. In this collection there are several bones of a very large species of that extraordinary carnivore described in a former section, (ante, p. 400,) the Machairodus, and of existing genera of mammalia, including Monkeys, Opossums, &c.; there are also shells of the large bulimus, a common terrestrial mollusk of South America.

There are likewise remains of a species of Hyena and Horse; the former genus, which abounded in Europe during the newer tertiary and drift period, is now only known to exist in Asia and Africa; and the latter was extinct in South America when the Spaniards invaded that country, though numerous relics occur of a species of Equus, that was contemporary with the colossal Edentata, whose skeletons are imbedded in the Pampas. Thus the ancient Brazilian fauna differs as essentially from the modern one, as that of the Cave period of Europe from the existing assemblage of terrestrial mammalia.

An interesting fact relating to the Brazilian caves is worthy of record. M. Claussen, in the course of his researches, discovered a cavern, the stalagmitic floor of which was entire. On penetrating the sparry crust he found the usual ossiferous bed, but pressing engagements compelled him to leave the deposit unexplored. After an interval of some years M. Claussen again visited the cavern, and found the excavation he had made completely filled up with stalagmite, the floor being as entire as on his first entrance. On breaking through this newly formed incrustation, it was found to be distinctly marked with lines of dark-coloured sediment, alternating with the crystalline stalactite. Reasoning on the probable cause of this appearance, M. Claussen sagaciously concluded that it arose from the alternation of the wet and dry seasons. During the drought of summer, the sand and dust of the parched land were wafted into the caves and fissures, and this earthy layer was covered during the rainy season by stalagmite, from the water that percolated through the limestone, and deposited calc-spar on the floor. The number of alternate layers of spar and sediment tallied with the years that had elapsed since his first visit; and on breaking up the ancient bed of stalagmite, he found the same natural register of the annual variation of the seasons; every layer dug through presented a uniform alternation of sediment and spar: and as the botanist ascertains the age of an ancient dicotyledonous tree from the annual circles of growth, in like manner the geologist attempted to calculate the period that had elapsed since the commencement of these ossiferous deposits of the cave; and although the inference, from want of time and means to conduct the inquiry with precision, can only be accepted as a rough calculation, yet it is interesting to learn, that the time indicated by this natural chronometer, since the extinct mammalian forms were interred, amounted to many thousand years.1

As in the bone-caves of England, France, and Germany, relics of human skeletons have been found in the upper layers of the detritus

1 Communicated to me by Mr. Waterhouse.

forming the floor of the Brazilian caves. Dr. Lund, from the condition and situation of these remains, concluded that they belonged to an ancient tribe that was coeval with some of the extinct mammalia. Portions of human crania from these caverns are placed with the Guadaloupe skeleton in Wall-case D.

OSSIFEROUS CAVES OF TORQUAY AND KIRKDALE.-Wall-case E.-The contents of this Case consist of mammalian remains from the caves of Kirkdale in Yorkshire, Kent's Hole, near Torquay in Devonshire, and of Gailenreuth in Franconia. The nature of such accumulations has already been so fully discussed (ante, p. 396), that a brief notice will suffice. The fossils belong for the most part to extinct species and genera of carnivora. In the upper part of the cabinet there are many fine teeth and jaws of the usual cave Hyenas and Bears; and teeth of the large tiger-like animal, the Machairodus latidens, described in a former chapter (ante, p. 400). There are likewise jaws and teeth of Foxes, Weasels, Rats, Mice, &c., from Kirkdale Cave; and of a species of Badger, Otter, Polecat, and Stoat, from Kent's Hole, Torquay; the latter are part of the collection of the late Rev. J. Mac Enery.

The cave at Torquay is an extensive chasm in the limestone strata, extending 600 feet in length, with many lateral fissures. The lower part of the cave is filled up to a thickness of twenty feet with reddish sandy loam, full of fossil bones of carnivorous animals. This is covered by a layer of stalagmite, a few feet thick, which forms the floor of the cavern. Upon this is a slight covering of earthy matter, in which have been found patches of charcoal, a few human bones, and fragments of coarse ancient pottery. Upon breaking through the sparry floor the ossiferous deposit is exposed; and imbedded with the fossil bones several flint-knives, stone arrow and spear-heads, were discovered. These instruments are of the same kind as those found in the early British tumuli on the adjacent hills, and unquestionably belong to the same period.

These facts have given rise to much curious speculation as to the contemporaneity of these remains of man and human art, with the extinct species of animals whose bones are entombed in the cave. Kent's Hole, Banwell Cave, and all the ossiferous fissures and caverns I have examined, appear to me to have been mere rents in limestone rocks, which were filled with drift while submerged in shallow water; and into which the mutilated carcasses of land animals may have been carried by subaqueous currents. As the bones, though broken, are rarely waterworn, and the fragments even retain their sharp edges, they must have been more or less protected by the muscles and skin; and the extreme freshness of the surface of many of the specimens supports this opinion. Upon the elevation of the land, these caves were raised above the water, and gradually drained, during which the formation of stalagmite commenced from the percolation of solutions of calcite through the superincumbent beds of limestone. As soon as Kent's Cave was accessible from the land, and before the formation of the stalagmitic

1 See Dr. Buckland's “Reliquiæ Diluvianæ,” for details; and “Wonders of Geology," 6th. Edit. p. 181, for a concise view of the phenomena.

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