[49] “Some Account of the Remains of the Megatherium sent to England from Buenos Ayres, by Woodbine Parish, Jun., Esq., F.R.S.,” by Wm. Clift, Esq., F.R.S., Geological Transactions, second series, vol. iii. p. 437.
CAST OF A SKELETON OF MEGATHERIUM AMERICANUM.
Set up in the Natural History Museum.
This and other parts having been carried to Buenos Ayres by the country people, were placed at the disposal of Sir Woodbine Parish by Don Hilario Sosa, the owner of the property on which the bones were found. A further inquiry was instituted by Sir Woodbine; and on his application, the governor granted assistance, the result of which was the discovery of the remains of two other skeletons on his Excellency’s properties, at no great distance from the place where the first had been found. It was in the year 1832 that Sir Woodbine Parish sent his valuable collection of bones from Buenos Ayres, and presented them to the Royal College of Surgeons. These specimens formed the subject of Mr. Clift’s memoir above quoted. But even then the materials were not complete for a thorough knowledge of the bony framework of the Megatherium, and it was not till 1845, when more remains (discovered near Luxan, 1837) reached this country, that Professor Owen was able to clear up one or two doubtful details. These were purchased by the trustees of the British Museum, and casts of the bones were taken. Among the various writings by learned men on the subject, Professor Owen’s masterly description stands pre-eminent; indeed, he was the only one to solve the riddle, to thoroughly explain the structure of this giant sloth, and to show how its food was obtained.[50] Neither Cuvier, nor the German doctors, nor Mr. Clift had succeeded in so doing.
[50] His views are expounded in his Memoir on the Megatherium, or Giant Ground Sloth of America, 1861, which is beautifully illustrated. The Royal Society gave £100 (part of a Government grant of £1000) to enable Professor Owen to carry out this important work.
In the Natural History Museum (Stand O, Gallery No. 2 on plan) is a cast representing the animal nearly erect, and grasping a tree. This magnificent cast (see [Plate XVII.]) represents an animal eighteen feet in length, and its bones are more massive than those of the elephant. For instance, the thigh-bone is nearly thrice the thickness of the same bone in the largest of existing elephants, the circumference being equal to the entire length. To a comparative anatomist several striking indications of great strength present themselves; thus, not only the very forms of the bones themselves mean strength, but their surfaces, ridges, and crests are everywhere made rough for the firm attachment of powerful muscles and tendons. In the fore part of the body the skeleton is comparatively slender, but the hind quarters show enormous strength and weight combined. The tail, also, is very powerful and massive. The fore limbs are long, and evidently constructed for the exertion of great force. How this force was applied we shall see presently. In both sets of limbs we notice powerful claws, such as might be used for scratching up the ground near the roots of a tree, and it was at one time thought that this was the way in which the creature obtained its leafy food, namely, by digging up trees by the roots and then devouring the leaves. But Professor Owen had another explanation.
As in the living sloths and armadillos (edentata[51]), there are no teeth in the fore part of the jaw. The molar teeth, of which there are five on each side of the upper jaw, and four in the lower, are hollow prismatic cylinders, straight, seven to nine inches long, and implanted in deep sockets. There are no other teeth, but these are composed of different substances, and so arranged that, as the tooth wears, the surface always presents a pair of transverse ridges, thus producing a dental apparatus well suited for grinding up vegetable food. In the elephants, which live on similar food, the grinding is effected by great molar teeth, which are replaced by new ones as the old ones are worn away. In the Megatherium, however, only one set of teeth was provided; but these, by constant upward growth, and continual addition of new matter beneath, lasted as long as the animal lived, and never needed to be renewed.
[51] This word, which means toothless, is misleading. All the edentata, however, agree in having no front, or incisor, teeth.