CLASS REPTILIA 



419 



Figure 290. Boa constrictor in action. As this picture proves, the snake really deserves its 

 name. It captured the deer, which it squeezed to death in its coils. Arrow indicates the point on 

 the deer to which it had been swallowed when the photographer started preparations for taking 

 the picture. Fear of man caused the snake to disgorge as much of the deer as possible before 

 the shutter clicked. This boa is a native of tropical America; it has a length of from 10 to 15 feet. 

 (Courtesy of James M. Keller and Clark Zeek.) 



Venomous (poisonous) reptiles will be 

 considered in a later section. 



Crocodilians 



Crocodilians are lizardlike in form, but 

 the jaws are extended into a long snout. 



The nostrils are at the end of the snout and 

 the eyes protrude from the head so that the 

 crocodilians can float at the surface with 

 only these parts above water. The skin is 

 thick and leathery, covered with horny 

 epidermal scales, and with dorsal and some- 

 times ventral bony plates somewhat like 



