14 GUIDE TO THE FOSSIL REPTILES, AMPHIBIANS, FISHES. 
Wall-case both above and below, but must also have been essentially 
Table-cases rQar * ne an i ma -l s - The Lower Jurassic crocodiles ( Teleosaurus , 
11,12. Pelagosaurus , and Mystriosaurus) are similarly armoured' 
The scutes of the back are in one paired series, while those 
of the belly are smaller and polygonal, forming a plate of 
mosaic. Teleosaurus has very slender jaws with sprawling 
interlocking teeth, and is represented by several instructive 
fragments from the Great Oolite of Normandy and the 
Fig. 9. —Skull of Pelagosaurus typus, from the Upper Lias of Normandy ; 
one-quarter nat. size. Right side-view, upper view, and palate. E. 
opening of median eustachian canal; N. posterior nares; 0. orbits; 
P. palatine vacuities ; T. supratemporal fossae ; V. basioccipital bone. 
(After Owen. Table-case 12.) 
Stonesfield Slate of England (Wall-case 3, Table-case 11). 
Pelagosaurus (Fig. 9), with equally slender jaws, is known 
by good skeletons from the Upper Lias of England, France, 
and Germany. Fragmentary remains of a small species, 
P. tyjpus, from Normandy, in Table-case 12, are specially 
valuable as illustrating the chief features of its bones; and 
a model of a complete skeleton of the same species, exhibited 
in the Department of Zoology, Gallery of Eeptiles, illustrates 
the general form and proportions of the reptile. The 
