EDENTATA. 303 



ous construction, walked, like the existing Ant-eaters and 

 Sloths, upon the outside edge of the fore-feet, with the claws 

 more or less bent inwards towards the palm of the hand. 

 The skull is small, as is the brain-case proper ; and the zygoma 

 has a strong descending process, similar to that of the same 

 bone in the true Sloths (fig. 610). As in the great majority 

 of the Edentate order, incisor and canine teeth are entirely 

 wanting, the front of the jaws being toothless. The jaws, 

 however, are furnished with five upper and four lower molar 

 teeth on each side. These grinding teeth are from seven to 

 eight inches in length, in the form of four-sided prisms, the 

 crowns of which are provided with well-marked transverse 

 ridges ; and they continue to grow during the whole life of 

 the animal. There are indications that the snout was pro- 

 longed, and more or less flexible ; and the tongue was prob- 

 ably prehensile. From the characters of the molar teeth it 

 is certain that the Megathere was purely herbivorous in its 

 habits ; and from the enormous size and weight of the body 

 it is equally certain that it could not have imitated its 

 modern allies, the Sloths, in the feat of climbing, back down- 

 wards, amongst the trees. It is clear, therefore, that the 

 Megathere sought its sustenance upon the ground ; and it 

 was originally supposed to have lived upon roots. By a 

 masterly piece of deductive reasoning, however. Professor 

 Owen showed that this great " Ground-sloth " nnist have 

 truly lived upon the foliage of trees, like the existing Sloths 

 — but with this difference, that instead of climbing amongst 

 the branches, it actually uprooted the tree bodily. In this 

 tour de force,, the animal sat upon its huge haunches and 

 mighty tail, as on a tripod, and then grasping the trunk with 

 its powerful arms, either wrenched it up by the roots or 

 broke it short off above the ground. Marvellous as this may 

 seem, it can be shown that every detail in the skeleton of 

 the Megathere accords with the supposition that it obtained 

 its food in this way. Though principally South American, 

 the genus Megatherium extended its range to North America, 

 this continent having yielded the remains of a species closely 

 allied to, or absolutely identical with, M. Cuvieri. 



The genus Mylodon comprises large Sloth-like animals, of 



