INTESTINAL STRUCTURE. 187 
SECTION V. 
INTESTINAL STRUCTURE OF ICHTHYOSAURUS 
AND OF 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 appa- 
ratus 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 disco- 
very within their skeletons, of the half digested 
remains of fishes and reptiles, which they had 
devoured, (see PI. 13, 14,), and by the further 
