SECTION V.
INTESTINAL STRUCTURE OF ICHTHYOSAURUS AND FOSSIL FISHES.
From the teeth and organs of locomotion, we come next
to consider those of digestion in the Ichthyosaurus. If there
be any point in the structure of extinct fossil animals, as to
which it should have seemed hopeless to discover any kind
of evidence, it is the form and arrangement of the intestinal
organs; since these soft parts, though of prime importance
in the animal economy, yet being suspended freely within
the cavity of the body, and unconnected with the skeleton,
would leave no traces whatever upon the fossil bones.
It is impossible to have seen the large apparatus of teeth, and strength of jaws, which we have been examining in the Ichthyosauri, without concluding that animals furnished with such powerful instruments of destruction, must have used them freely in restraining the excessive population of the ancient seas. This inference has been fully confirmed by the recent discovery within their skeletons, of the half digested remains of fishes and reptiles, which they had devoured, (see Pl. 13, 14,) and by the further discovery of Coprolites, (see Pl. 15,) i. e. of fœcal remains in a state of petrifaction, dispersed through the same strata in which these skeletons are buried. The state of preservation of these very curious petrified bodies is often so perfect, as to indicate not only the food of the animals from which they were derived, but also the dimensions, form, and structure of their stomach, and intestinal canal.[1]
- ↑ The following description of these Coprolites, is given in my memoir on this subject, published in the Transactions of the Geological
