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ZOOLOGY 



Horned toad. Note the protective resemblance. 



tation. The iguana of Central America and South America is 

 among the largest of lizards, growing to a length of three feet or 

 more. It has the distinction of being one of the few edible lizards. 

 Snakes. — Probably the most disliked and feared of all animals 

 are the snakes. This feeling, however, is rarely deserved. Our 



common snakes are harm- 

 less and were it not for 

 the fact that they live 

 upon insect - destroying 

 animals, as toads, frogs, 

 and birds, we might even 

 say that they are useful 

 to man. 



Snakes are almost the 

 only legless vertebrates. 

 Although the limbs are 

 absent, still the pelvic and 

 pectoral girdles are de- 

 veloped. The Yevy long 

 backbone is made up of a 

 large number of vertebrae, 

 as many as four hundred 

 being found m the boa constrictor. Ribs are attached to all ver- 

 tebrae in the region of the body cavity. 



Rattlesnake three feet long coiled ready to strike. 

 In this position it can dart its head forward two 

 feet only. From photograph by Davison. 



