SO MAEINE EEPTILES OF THE OXFOED CLAY. 



Order CROCODILIA. 



Lacertiform reptiles, mostly of large size. Skull with fixed quadrates, upper and 

 lower temporal arcades, and a secondary palate formed posteriorly by the palatines (in 

 the Mesosuchia) or by the palatines and pterygoids (in the Eusuchia) ; no parietal 

 foramen. Teeth confined to the margins of the jaws and implanted in deep sockets. 

 Vertebrae amphiccelous, amphiplatyan, or procoelous. Cervical ribs mostly short, with 

 double heads articulating with processes of the neural arch and centrum ; dorsal ribs 

 articulating by their head and tubercle with the transverse processes of the neural 

 arch only. Two sacral vertebrae. Dermal ossifications usually present. 



Suborder Mesosuchia. 



Internal nares opening at the hinder end of the secondary palate formed by the 

 palatines, the pterygoids having no ventral processes. The lateral eustachian passages 

 forming open grooves on the basisphenoid. Vertebrae amphiccelous or amphiplatyan. 



Family TELEOSAUFJD.E. 



Mesosuchia with a greatly elongated rostrum formed mainly by the maxillae, the 

 premaxillae being small and separated by a long interval from the anterior end of 

 the nasals. The prefrontals are small and do not form an overhanging roof to the 

 orbit, which is round or oval in outline and looks mainly upwards, but to some extent 

 also outwards and forwards. The lachrymal is large. Supratemporal fossae tending to 

 become very large and longer than wide. Fore limb much smaller than hind limb. 

 Two rows of keeled dorsal scutes, numerous ventral scutes. 



Lias to (?) Upper Cretaceous. 



Genus STENEOSAURUS, Geoffroy (emend. Deslongchamps). 



[Memoires du Museum, vol. xii. p. 146 (1825) ; emend. E. E. Deslongchamps, 

 Notes Paleontologiques, p. 12G (Caen, 1867).] 



1837. Leptocranius, Bronn, Leth. Geogn. i. p. 516. 



1845. Sericodon {Sericosaurus in index), van Meyer, Neues Jahrb. f. Min. etc. p. 310. 



Premaxillary region expanded and bearing the united anterior narial openings. 

 Orbits completely surrounded by bone, usually nearly circular in outline, and 



