Fig. 191.—Skull of Scelidotherium.

The lower jaw-bone of Mylodon, which Mr. Darwin discovered at the base of the cliff called Punta Alta, in Northern Patagonia, had the teeth entire on both sides; they are implanted in deep sockets, and only about one-sixth of the last molar projects above the alveolus, but the proportion of the exposed part increases gradually in the inner teeth ([Fig. 191]).

“The habits of life of these Megatheroid animals were a complete puzzle to naturalists, until Professor Owen solved the problem with remarkable ingenuity. The teeth indicate, by their simple structure, that these Megatheroid animals lived on vegetable food, and probably on the leaves and small twigs of trees; their ponderous forms and great strong curved claws seem so little adapted for locomotion, that some eminent naturalists have actually believed that, like the Sloths, to which they are intimately related, they subsisted by climbing back downwards, on trees, and feeding on the leaves. It was a bold, not to say preposterous idea to conceive even antediluvian trees with branches strong enough to bear animals as large as elephants. Professor Owen, with far more probability, believes that, instead of climbing on the trees, they pulled the branches down to them, and tore up the smaller ones by the roots, and so fed on the leaves. The colossal breadth and weight of their hinder quarters, which can hardly be imagined without having been seen, become, on this view, of obvious service instead of being an encumbrance; their apparent clumsiness disappears. With their great tails and their huge heels firmly fixed like a tripod in the ground, they could freely exert the full force of their most powerful arms and great claws. The Mylodon, moreover, was furnished with a long extensile tongue, like that of the giraffe, which by one of those beautiful provisions of Nature, thus reaches, with the aid of its long neck, its leafy food.”[102]

XXVIII.—Ideal European Landscape in the Quaternary Epoch.