The result of his researches, as recorded in the Ossemens Fossiles, has been to show that all fossil quadrupeds, however differing in generic or specific details, are uniformly constructed on the same general plan, and systematic basis of organization as living species; and that throughout the various adaptations of a common type to peculiar functions, under different conditions of the earth, there prevails such universal conformity of design, that we cannot rise from the perusal of these inestimable volumes, without a strong conviction of the agency of one vast and mighty Intelligence, ever directing the entire fabric, both of past and present systems of creation.
Nothing can exceed the accuracy of the severe and logical demonstrations, that fill these volumes with proofs of wise design, in the constant relation of the parts of animals to one another, and to the general functions of the whole body. Nothing can surpass the perfection of his reasoning, in pointing out the beautiful contrivances, which are provided in almost endless variety, to fit every living creature to its own peculiar state and mode of life. His illustration of the curious conditions, and concurrent compensations that are found in the living Elephants, apply equally to the extinct fossil species of the same genus; and similar exemplifications may be extended from the living to the extinct species of other genera, e. g. Rhinoceros, Hippopotamus, Horse, Ox, Deer, Tiger, Hyæna, Wolf; &c. that are usually associated with the Elephant in the fossil state.
The animal I shall select for my present purpose is that most extraordinary fossil creature, the Megatherium, (see Pl. 5), an animal, in some parts of its organization, nearly allied to the Sloth, and, like the Sloth, presenting an apparent monstrosity of external form, accompanied by many strange peculiarities of internal structure, which have hitherto been but little understood.
The Sloths have afforded a remarkable exception to the conclusions which naturalists have usually drawn, from their
