It is curious to see to what a degree of perfection has been carried, in
our days, the knowledge of the antediluvian animals, their habits, and
their economy. Fig. 98 represents the skeleton of an Ichthyosaurus found
in the Lias of Lyme Regis, which still retains in its abdominal cavity
coprolites, that is to say, the residue of digestion. The soft parts of
the intestinal canal have disappeared, but the _fæces_ themselves are
preserved, and their examination informs us as to the alimentary
regimen of this animal which has perished from the earth many thousands,
perhaps millions, of years. Mary Anning, to whom we owe many of the
discoveries made in the neighbourhood of Lyme Regis, her native place,
had in her collection an enormous coprolite of the Ichthyosaurus. This
coprolite (Fig. 99) contained some bones and scales of Fishes, and of
divers Reptiles, well enough preserved to have their species identified.
It only remains to be added that, among the bones, those of the
Ichthyosaurus were often found, especially those of young individuals.
The presence of the undigested remains of vertebræ and other bones of
animals of its own species in the coprolites of the Ichthyosaurus
proves, as we have already had occasion to remark, that this great
Saurian must have been a most voracious monster, since it habitually
devoured not only fish, but individuals of its own race--the smaller
becoming the prey of the larger. The structure of the jaw of the
Ichthyosaurus leads us to believe that the animal swallowed its prey
without dividing it. Its stomach and intestines must, then, have formed
a sort of pouch of great volume, filling entirely the abdominal cavity,
and corresponding in extent to the great development of the teeth and
jaws.
[Illustration: Fig. 99.--Coprolite, enclosing bones of small
Ichthyosaurus.]
[Illustration: Fig. 100.--Coprolite of Ichthyosaurus.]
The perfection with which its contents have been preserved in the
fossilised coprolites, furnishes indirect proofs that the intestinal
canal of the Ichthyosaurus resembled closely that of the shark and the
dog-fish--fishes essentially voracious and destructive, which have the
intestinal canal spirally convoluted, an arrangement which is exactly
that indicated in some of the coprolites of the Ichthyosaurus, as is
evident from the impressions which the folds of the intestine have left
on the coprolite, of which Fig. 100 is a representation. In the cliffs
near Lyme Regis coprolites are abundant in the Liassic formation, and
have been found disseminated through the shales and limestones along
many miles of that coast.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Elsewhere in the archive
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account