CROCODILES. 



By S. W. WILLTSTON. 



The Crocodiles, inclusive of the Gavials and Alligators, are 

 the highest type of reptilian life now existent upon the earth. 

 It is almost impossible to state the number of species now living, 

 since authors are not agreed as to what the valid species are, 

 but they are found in nearly all the tropical and subtropical 

 regions of the earth. They include three distinct types or 

 groups : the Crocodiles, Alligators, Gavials or Gharials. The 

 last group is confined at the present time exclusively to the rivers 

 of the interior of India, in the hottest regions. They are dis- 

 tinctly more aquatic in their nature than are the other forms, and 

 are especially characterized by the great elongation and slen- 

 derness of their snout, armed with many sharp teeth. 



The Crocodiles are much more extensive in their range, occur- 

 ring in India, Africa, Australia, and the tropical parts of Amer- 

 ica. The head is broad and flat, the jaws are shorter and rounded 

 in front, and the powerful teeth are irregular in size. The Alliga- 

 tors are much more nearly like the Crocodiles than the Gavials. 

 Their head is broad and flat, as in the Crocodiles. They may 

 be distinguished by the large tooth of the lower jaw, sometimes 

 called the " canine." It is received into a pit or socket on the 

 upper jaw, and is not visible when the mouth is closed, while in 

 the Crocodiles it passes in a groove on the outside and is visible 

 when the mouth is closed. The teeth of the Alligator are received 

 on the inner side of the upper ones instead of between them, as 

 in the Crocodile. The Alligators, with one exception, which oc- 

 curs in China, are confined to the southern part of North Amer- 

 ica and the northern part of South America. 



Both the Crocodiles and Alligators are more amphibious in 

 habit than are the Gavials, and their teeth are better adapted 



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