CROCODILES AND ALLIGATORS. 9 



of which the ball is behind and the cup in front {procmlous). The 

 nostrils are situated at the extremity of the snout, and their posterior 

 openings (choance) carried back to the hinder extremity of the skull, the 

 palatine and pterygoid bones developing inferior plates, which meet in 

 the middle line and thus prolong the nasal passage. The armour con- 

 sists of more than one pair of longitudinal rows of plates on the back ; 

 on the under surface of the body armour may or may not be present. 



In common with Alligators and Caimans, true Crocodiles are Cases 1-2. 

 distinguished by the shortness and breadth of the muzzle, which is 

 either rounded-off or triangular, and the large and stout teeth, which 

 interlock with one another and are less numerous than in the 

 Gharials. The union (symphysis) between the two halves of the 

 lower jaw is also short, and does not include the splenial bone ; and 

 the nasal bones enter the aperture of the nostrils. In Crocodiles the 

 fourth lower tooth is received into a notch in the upper jaw (figs. 7 

 and 9), and the fifth upper tooth is the largest in the whole series. 

 The number of upper teeth ranges from 16 to 19, and there are 

 14 or 15 lower teeth on each side. There is no bony armour on 

 the under side of the body. 



Crocodiles have a much wider geographical distribution than 

 any other members of the order. Three species, Crocodilus cataphr ac- 

 tus (10), C.johnstoni (9), and C. intermedins, have longer and more 

 Grharial-like muzzles than the rest. Other species, like the American 

 Crocodile (C. americanus, 16), the Timsa, or Common African Croco- 

 dile {C. niloticus, 14), and the Indian Estuarine Crocodile (C. poro- 

 sus, 19), have somewhat shorter and broader muzzles. In a third 

 group, which includes the Muggar, or Indian Marsh-Crocodile 

 (C. palustris, 20), the muzzle is still broader and more Alligator- 

 like, and the pits in the temples are smaller than in the other 

 groups. One species, the West African Osteolamus tetraspis (3), 

 is assigned to a separate genus on account of the production of the 

 nasal bones to divide the aperture of the nostrils. 



Together with Alligators and Caimans, Crocodiles are the largest 

 and most ferocious of living reptiles ; the Indian G. porosus commonly 

 attaining a length of from 15 to 20 feet, and occasionally reaching 

 even larger dimensions. Most of the species frequent rivers, 

 marshes, or pools, but C. porosus inhabits estuaries, and may be 

 met with out at sea. Crocodiles are exclusively carnivorous, and 

 generally seize their victims (other than human beings) by the nose 

 as they are drinking. A large number of people — especially women, 

 as they go to the rivers for water — are annually killed in India by 



