Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 1.djvu/116

 112 might thus repose, moored to the margin of a lake or river, without the slightest muscular exertion, the weight of the head and body tending to fix and keep the tusks fast anchored in the substance of the bank; as the weight of the body of a sleeping bird keeps the claws clasped firmly around its perch. These tusks might have been further used, like those in the upper jaw of the Walrus, to assist in dragging the body out of the water; and also as formidable instruments of defence.

The structure of the scapula, already noticed, seems to show that the fore leg was adapted to co-operate with the tusks and teeth, in digging and separating large vegetables from the bottom. The great length attributed to the body, would have been no way inconvenient to an animal living in the water, but attended with much mechanical disadvantage to so weighty a quadruped upon land. In all these characters of a gigantic, herbivorous, aquatic quadruped, we recognise adaptations to the lacustrine condition of the earth, during that portion of the tertiary periods, to which the existence of these seemingly anomalous creatures appears to have been limited.

As it will be quite impossible, in the present Treatise, to give particular descriptions of the structure, even of a few of the fossil Mammalia, which have been, as it were, restored again to life by the genius and industry of Cuvier; I shall endeavour to illustrate, by the details of a single species, the method of analytical investigation, that has been applied by that great philosopher to the anatomy both of fossil and recent animals.