Among living voracious reptiles we have examples of stomachs equally capacious; we know that whole human bodies have been found within the stomachs of large Crocodiles; we know also, from the form of their teeth, that the Ichthyosauri, like the Crocodiles, must have gorged their prey entire; and when we find, imbedded in Coprolites derived from the larger Ichthyosauri, bones of smaller Ichthyosauri, of such dimensions, (see Pl. 15, Fig. 18. And Geol. Trans. 2, S. vol. iii, Pl. 29, Figs, 2, 3, 4, 5,) that the individuals from which they were derived, must have measured several feet in length; we infer that the stomach of these animals formed a pouch, or sac, of prodigious size, extending through nearly the entire cavity of the body, and of capacity duly proportioned to the jaws and, teeth with which it co-operated.
Spiral Disposition of Small Intestines.
As the more solid parts of animals alone, are usually susceptible of petrifaction, we cannot demonstrate by direct evidence the form and size of the small intestines of the Ichthyosauri, but the contents of these viscera are preserved in such perfection in a fossil state, as to afford circumstantial evidence that the bowels in which they were moulded, were formed in a manner resembling the spiral intestines of some of the swiftest and most voracious of our modern fishes.
We shall best understand the structure of these intestines by examining the corresponding organs of Sharks and Dog-fish, animals not less peculiarly rapacious among the inhabitants of our modern seas, than the Ichthyosauri were in those early periods to which our considerations are carried back. We find in the intestines of these fishes, Pl. 15, Figs. 1, and 2,) and also in those of Rays, an arrangement resembling that of the interior of an Archimedes screw, admirably adapted to increase the extent of internal
