We pass on into the third and lower division, and an entirely different class of existences now catch the eye. The huge mastodon, with his enormous length of body, and his tusks projecting from both upper and under jaw, stands erect in the middle of the floor,--a giant skeleton. We see beside him the great bones of the megatherium,--thigh bones eleven inches in diameter, and claw-armed toes more than two feet in length. There, too, ranged species beyond species, are the extinct elephants; and there the ponderous skull of the dinotherium, with the bent tusks in its lower jaw, that give to it the appearance of a great pickaxe, and that must have dug deeply of old amid the liliaceous roots and bulbs of the Tertiary lakes and rivers. There also are the massive heads and spreading horn-cores of the _Bos primigenius_, and the large bones and broad plank-like horns of the great Irish elk. And there too, in the same apartment, but leaning against its further wall,--last, as most recent, of all the objects of wonder in that great gallery,--is the famous human skeleton of Guadaloupe, standing out in bold relief from its slab of gray limestone. It occurs in the series, just as the series closes, a little beyond the mastodon and the mammoths; and, in its strange character as a fossil man, attracts the attention scarce less powerfully than the great Palæozoic plants, the great Secondary reptiles, or the great Tertiary mammals. [Illustration: Fig. 93. SKULL OF DINOTHERIUM GIGANTEUM. (_Miocene._)]