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Family. CROCODILIDA. Cuvier. 



CHARACTERS. 



1. The head is large, and covered with a thick, closely adherent skin. 



2. The nostrils are approximated, and open near the snout; they are furnished 

 with movable valves, and communicate with the fauces by a long narrow 

 canal. 



3. The eyes are protected by three lids. 



4. The external opening of the ear is furnished with two movable lips, one above, 



the other below, by which it can be closed. 



5. The mouth is very large, opening even behind the cranium. 



6. The tongue is fleshy, flat, closely adherent at its borders, and not at all pro- 



tractile. 



7. The teeth are simple, conical, pointed, hollow at their bases, of unequal size, 



and placed in a single row. 



8. The body is covered above with large, square plates, more or less carinated; 



those of the back are elevated in longitudinal ridges; the abdomen is protected 

 by large, square, and smooth plates. 



