ORDER CROCODILIA. 1 1 87 



are separated by a long interval from the premaxillae ; the orbits are 

 of regular contour, and directed more or less completely frontally ; 

 while the nares look more or less anteriorly. The dermal armour 

 is fully developed, and sclerotic plates were not present in the eye. 

 The type genus Teleosaurus comprises small or medium-sized species, 

 and is readily characterised by the teeth being inclined horizontally 

 outwards, and extremely numerous. It is confined to the Lower 

 Jurassic, and is abundant in the Stonesfield slate of Oxfordshire, 

 and the nearly equivalent beds of Caen, in Normandy. The most 

 abundant genus is, however, Steneosaurus (fig. 1085), in which 

 Mystriosanrus may be included, characterised by the elongated 

 snout, the nearly vertical direction of the teeth, and the large size 

 of the supratemporal fossae, which in some species attain enormous 

 dimensions. In the Liassic forms, separated generically by some 

 writers as Mystrtosaurus, the orbits are somewhat oblique, and the 

 supratemporal fossae are never excessively large ; but in the numer- 

 ous species of the Lower and Middle (Oxford Clay) Jurassic the 

 direction of the orbits is entirely frontal, and the supratemporal 

 fossae are very large. In the figured S. Heberti, of the Lower part 

 of the Oxford Clay, the skull is somewhat intermediate in these 

 respects ; the orbits being slightly oblique, and the supratemporal 

 fossae large. This genus does not appear to have survived above 

 the Kimeridge Clay. In Pelagosaurus (fig. 1086) we have an 



FFmrm^ft 





Fig. 1086. — Right lateral view of the skull of Pelagosaurus typus; from the Upper Lias of 

 Normandy. Reduced. T, Supratemporal fossa ; O, Orbit. 



allied genus, represented only by two species of Liassic age ; it is 

 distinguished from the preceding by several characters ; but more 

 especially the form of the posterior nares, and the smaller and 

 rounded supratemporal fossae. The remains of the small P. typus 

 are especially abundant in the Upper white Lias of Normandy, and 

 the marvellously perfect preservation of some of the skeletons has 

 enabled the bony anatomy of this species to be as completely 

 studied as in the case of an existing form. In Machimosaurus, of 

 the Kimeridge Clay (Upper Jurassic) of both England and the 

 Continent, and Teleidosaurus, of the Fullers' Earth (Lower Jurassic) 

 of Normandy, we have two genera in which the skull becomes much 

 shorter and broader, the teeth stouter and less numerous, and the 

 orbits more oblique ; and which thus connect the present with the 



