CLASS REPTILIA. . 



quadrate, outer irregularly scattered; nuchal scales six. 

 West Indies. 



Armed Crocodile. Crocodilus Cataphr actus, Cuv. Oss. 



Foss. f. 

 Head produced ; nape with four bands of bony shields like 

 the Alligators. Mus. Col. Surgs. 



Flat-headed Crocodile. Croc. Planirostris, Graves. 



Head, base, flat ; shields tubercular ; nuchal plates six, dis- 

 tant. Africa ? 



Intermediate Crocodile. Crocodilus Intermedius, Graves. 



Head produced, sub-cylindrical ; dorsal shields, six-rowed, 

 nuchal, six. America ? 



III. Head long, produced, muzzle cylindrical ; teeth and 

 feet like Crocodiles. Gavialis. 



Common Gavial. Croc. (Gavialis) Gangeticus. 



The nuchal shield united to the dorsal plates ; the crown 

 and orbits appear to dilate with age. See Faugas. Hist. 

 IMont. St. Petri, t. 46, 48 ; from whence Croc Tenuirostris, 

 Cuv. Ganges. 



Order III. ? Enaliosauri. Conyheare. 



Vertebrae of the back and the ribs free, mobile ; the mouth 

 toothed ; the feet fin-shaped. Only found in the fossil state ; 

 perhaps not of this section. 



Gen. 1. IcHTHYSAURus, Koenig. 



Head large ; teeth conical, placed in a groove ; neck short. 



For the anatomy and species of this genus, consult Home 

 Phil. Trans. Conybear. Geolog. Trans, and Cuv. Os. Fos. 

 vol 5. 



Ichthyosaurus Communis, Conybeare. Cuv. Os. Fos. t. 29. 



f.1,9. 



23 



