XXVII.—Skeleton of the Megatherium (Clift).
If we cast a glance at the skeleton figured on the opposite page ([Plate XXVII.]), which was found in Paraguay, at Buenos Ayres, in 1788, and which is now placed, in a perfect state of preservation, in the Museum of Natural History in Madrid, it is impossible to avoid being struck with its unusually heavy form, at once awkward as a whole, and ponderous in most of its parts. It is allied to the existing genus of Sloths, which Buffon tells us is “of all the animal creation that which has received the most vicious organisation—a being to which Nature has forbidden all enjoyment; which has only been created for hardships and misery.” This notion of the romantic Buffon is, however, altogether incorrect. An attentive examination of the Animal of Paraguay shows that its organisation cannot be considered either odd or awkward when viewed in connection with its mode of life and individual habits. The special organisation which renders the movements of the Sloths so sluggish, and apparently so painful on level ground, gives them, on the other hand, marvellous assistance when they live in trees, the leaves of which constitute their exclusive food. In the same manner, if we consider that the Megatherium was created to burrow in the earth and feed upon the roots of trees and shrubs, every organ of its heavy frame would appear to be perfectly appropriate to its kind of life, and well adapted to the special purpose which was assigned to it by the Creator. We ought to place the Megatherium between the Sloths and the Anteaters. Like the first, it usually fed on the branches and leaves of trees; like the latter, it burrowed deep in the soil, finding there both food and shelter. It was as large as an Elephant or Rhinoceros of the largest species. Its body measured twelve or thirteen feet in length, and it was between five and six feet high. The engraving on page 403 ([Plate XXVII.]) will convey, more accurately than any mere verbal description, an idea of the form and proportions of the animal.
The English reader is chiefly indebted to the zeal and energy of Sir Woodbine Parish for the materials from which our naturalists have been enabled to re-construct the history of the Megatherium. The remains collected by him were found in the river Salado, which runs through the flat alluvial plains called Pampas to the south of the city of Buenos Ayres. A succession of three unusually dry seasons had lowered the waters to such a degree as to expose part of the pelvis to view, as the skeleton stood upright in the mud forming the bed of the river. Further inquiries led to the discovery of the remains of two other skeletons near the place where the first had been found; and with them an immense shell or carapace was met with, most of the bones associated with which crumbled to pieces on exposure to the air. The osseous structure of this enormous animal, as furnished by Mr. Clift, an eminent anatomist of the day, and under whose superintendence the skeleton was drawn, must have exceeded fourteen feet in length, and upwards of eight feet in height. The deeply shaded parts of the figure show the portions which are deficient in the Madrid skeleton.
Cuvier pointed out that the skull very much resembled that of the Sloths, but that the rest of the skeleton bore relationship, partly to the Sloths, and partly to the Anteaters.
The large bones, which descend from the zygomatic arch along the cheek-bones, would furnish a powerful means of attaching the motor muscles of the jaws. The anterior part of the muzzle is fully developed, and riddled with holes for the passage of the nerves and vessels which must have been there, not for a trunk, which would have been useless to an animal furnished with a very long neck, but for a snout analogous to that of the Tapir.
The jaw and dental apparatus cannot be exactly stated, because the number of teeth in the lower jaw is not known. The upper jaw, Professor Owen has shown, contained five molars on each side; and from comparison and analogy with the Scelidotherium it may be conjectured that the Megatherium had four on each side of the lower jaw. Being without incisors or canines, the structure of its eighteen molars proves that it was not carnivorous: they each resemble the composite molars of the Elephant.
Fig. 186.—Skeleton of Megatherium foreshortened.