ANIMALS CLASSIFIED 



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Order III. Ophidia (snakes). Body 

 elongated, covered with scales. No 

 limbs present. Examples : garter 

 snake, rattlesnake. 



Order IV. Crocodilia. Fresh-water 

 reptiles with elongated body and 

 bony scales on skin. Two-paired 

 limbs. Examples : alligator, crocodile. 



The common garter snake. Reduced 

 to about one tenth natural size. 



Birds. — Birds among all other 

 animals are known by their cov- 

 ering of feathers and the presence of wings. The feathers are de- 

 veloped from the skin. These aid in flight, and protect the body 

 from the cold. 



Adaptations in the bills of birds. Could we tell anything about the food of a bird 

 from its bill ? Do these birds all get their food in the same manner ? Do 

 they all eat the same kind of food ? 



The form of the bill in particular shows adaptation to a wonder- 

 ful degree. A duck has a flat bill for pushing through the mud and 

 straining out the food ; a bird of prey has a curved or hooked beak 

 for tearing ; the woodpecker has a sharp, straight bill for piercing 

 the bark of trees in search of the insect larvae which are hidden 

 underneath. Birds do not have teeth. 



