32 GUIDE TO THE FOSSIL REPTILES, AMPHIBIANS, FISHES. 
Table-ease 
30. 
Wall-cases 
11-14. 
Table-cases 
24-29. 
Cases P, Q. 
Cases P, Q. 
plates extending over the palate, and would doubtless be used 
for crushing shell-fish. Good examples are exhibited in 
Table-case 30. 
Order YII.— SAUROPTERYGIA. 
A group of aquatic reptiles closely related both to the 
extinct Anomodontia and to the surviving Chelonia was 
abundantly represented in all the seas of the Mesozoic 
period. It is known as the Order Sauropterygia (“ lizard- 
finned ”) because the swimming paddles in all its representa¬ 
tives comprise only the usual four or five reptilian toes, 
which are not supplemented by other little bones as in 
the paddles of the contemporary Ichthyopterygia (see p. 37). 
Fig. 28.—Hinder neck-vertebra of Plesiosaurus, front and side views, from 
the Lower Lias of Lyme Eegis; two-thirds nat. size. pr.z. prezyga- 
pophysis; jpt.z. postzygapophysis. (Table-case 27.) 
The general characters of the Order are especially well shown 
by the skeletons of Cryptoclidus in Cases P, Q, while more 
technical points are illustrated in Table-cases 24 to 29. 
The head varies in size, but is usually small, and the conical 
teeth are fixed in deep sockets round the margin of the jaws. 
The vertebrae (Fig. 28) are slightly biconcave. Although the 
neck is always distinct and often long and slender, it must have 
