FAUNA OF THE POST-PLIOCENE. 351 
towards the palm of the hand. 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 proba- 
bly 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 downwards, 
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” must have truly lived upon the 
foliage of trees, like the existing Sloths—but with this differ- 
ence, that instead of climbing amongst the branches, it actually 
uprooted the tree bodily. In this four 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. Similar 
habits were followed by the allied AZylodon (fig. 261), another 
of the great ‘‘ Ground-Sloths,” which inhabited South America 
during the Post-Pliocene period. In most respects, the JZ}/o- 
don is very like the Megathere; but the crowns of the molar 
teeth are flat instead of being ridged. The nearly-related 
genus AZegalonyx, unlike the Megathere, but like the Mylodon, 
extended its range northwards as far as the United States. 
Just as the Sloths of the present day were formerly repre- 
sented in the same geographical area by the gigantic Megathe- 
roids, so the little banded and cuirassed Armadillos of South 
America were formerly represented by gigantic species, con- 
stituting the genus Glyptodon. The Glyptodons (fig. 262) 
differed from the living Armadillos in having no bands in 
their armour, so that they must have been unable to roll 
themselves up. It is rare at the present day to meet with any 
Armadillo over two or three feet in length; but the length of 
