REPTILIA 



309 



Order Crocodilia. — Alligators, crocodiles, and caimans, like the 

 turtles, have an oval cloacal opening, immovable quadrate bones, 

 and bony plates in the skin. They differ in structure from all other 

 reptiles although their shape is hzard-like. They have abdominal 

 ribs and abdominal sternum. Their teeth are placed in sockets. 

 The heart is completely four-chambered. 



The Chinese alligator {Alligator sinensis) lives in the Yang-tse 

 Kiang in China. It is a small species, greenish black, with yellow 

 spots. It is the nearest living relative of the American alligator. 



The American alligator {Alligator mississippiensis) is found as 

 far north as North Carolina. It may reach a length of 16 feet 3 

 inches. It is the only crocodilian that bellows. It is much less 

 vicious than the crocodiles. Alligators are sold to tourists, and 

 there is a constant demand for their hides, used for bags and pocket- 

 books. Alligator farms supply animals to the cinema producers. 



The caimans of South America are quite vicious. Gavials, 

 found in India, may reach a length of thirty feet, and are quite 

 ferocious, but rarely attack man. (Figure 167.) 



The salt water crocodile and the mugger of India and the sacred 

 African crocodile ^ are extremely dangerous animals and cause many 

 deaths annually. An American crocodile, resembling the African 

 form, was found in Florida in 1875, ^1 I^^. W. T. Hornaday. It 

 is extremely vicious. 



Order Squamata. {Super-Order F/.)— This order includes two 

 sub-orders, Lacertiliay or lizards, and Opkidia, or snakes. The 

 Squamata (Lat. squamatus, a scale) have horny scales, renewed 

 periodically, movable quadrate bones, a transverse cloacal opening 

 and paired penes. 



Sub-Order Lacertilia. (Lat. lacertus, a lizard.) — The lizards, 

 chameleons and iguanas have certain characteristics distinguishing 

 them from the snakes and the crocodilia. Lacertilia have paired 

 appendages or rudiments, scaled ventral surface, tympanic mem- 

 branes, a sternum (usually) and movable eyelids. 



The blind-worm, or slow-worm, a limbless lizard {Anguis Jragilis) 

 found in Europe and Asia, is a most snaky animal. Its body is 

 covered with smooth round scales and its locomotion resembles that 



1 " The crocodile is esteemed sacred by some of the Egyptians, by others he is 

 treated as an enemy, and the people of Elephantine even eat their flesh. The 

 lonians called the Egyptian ' Champsae ' crocodiles, after the wall-lizards of Ionia." 

 (Hereodotus II, 69.) The name Champsae remains today in the Coptic language. 



