168 
MARINE SAURIANS. 
with the mummies of Men, and Apes, and Cro- 
codiles, concludes them to he the remains of 
mammalia and reptiles, that have formed part 
of an ancient population on the banks of the 
Nile. 
SECTION iV. 
ICHTHYOSAURUS. 
Nearly at the head of the surprising disco- 
veries, which have been made relating to the 
family of Saurians, we may rank the remains 
of many extraordinary species, which inhabited 
the sea; and which present almost incredible 
combinations of form, and structure ; adapting 
them for modes of life, that do not occur among 
living reptiles. These remains are most abun- 
dant throughout the lias and oolite formations 
of the secondary series.* In these deposits we 
* The chief repository in which these animals have been found 
is the lias, at Lyme Regis ; but they abound also along the whole 
extent of this formation throughout England, e. g. from the 
coast of Dorset, through Somerset and Leicestershire, to the 
coast of Yorkshire : they are found also in the lias of Germany 
and France. The range of the genus Ichthyosaurus seems to have 
begun with the Muschelkalk, and to have extended through the 
whole of the oolitic period into the cretaceous formation. The 
most recent stratum in which any remains of this genus have vet 
been found is the chalk marl at Dover, where they have been 
discovered by Mr. Mantell: I have found them in the gault, 
near Benson, Oxon. 
