CLASS REPTILIA. 



quadrate, outer irregularly scattered; nuchal scales six. 

 West Indies. , 



Armed Crocodile. Crocodilus Cataphractus, 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 ; uuchal 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. 

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

 Cuv. Ganges. 



Order III. ? Enaliosauei. 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 anaton.y and species of this genus, consult Home 

 Phil. Trans. Conybear. Geolog. Trans, and Cuv. Os. Fo&. 

 vol 5. 



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

 f.1,9. 



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