66 
ICHTIIYOSA URIA FROM THE 
ICHTH Y OSAURIA 
FROM THE CAMBRIDGE UPPER GREENSAND. 
Exhibited in Drawers of Compartment f of Cabinet J. 
Case. Comp. Drawer. Specimen. 
J f i 1—398 Teeth, from many different individuals, 
presenting every attainable modification 
of size and form. It has not been found 
possible to recognise more than one 
specific shape; and as no characteristic 
teeth of Plesiosaurus have ever been 
found it has been suspected that while 
this form of tooth, known as Ichthyo¬ 
saurus campylodon, must have been 
common to several species of Ichthyo¬ 
saurus, it may also have pertained to 
some Plesiosaurs. 
J 
f ii 1—43 The whole of the vertebrae in this drawer 
are from the terminal part of the tail. 
44—46 They are quite unlike the ordinary type 
47—50 of Ichthyosaurus. The larger specimens 
make an approximation to the form of 
51, 52 the caudal vertebrae in Cetaceans, and 
53—56 were formerly supposed to be the verte- 
57, 58 brae of whales. They are sub-circular, 
59—61 with a small central depression on the 
62—65 articular intervertebral face of the cen- 
67—70 trum, which has its outer part tumid, 
