REPTILIA (REPTILES). 



The living reptiles closely simulate the Batrachia, and 

 in fact the frogs, toads, and salamanders are reptiles in 

 popular parlance. The short- 

 bodied turtles are paralleled by the 

 frogs, the lizards by the sala- 

 manders, and the snakes by the 

 blindworms. Yet the differences 

 between the two groups are many 

 and important. 



The body is more or less 

 completely covered with scales, 

 and the toes, when present, bear 

 claws. The scales differ from 

 those of fishes in being outside 

 of the outer layer of the skin. 

 These scales differ much in ar- 

 rangement, etc. The large plates 

 covering the carapace of the turtle 

 are but enlarged scales, while the 

 bony armor of the alligator is 

 composed of scales, rendered more 

 protective by the development of 

 bone in the deeper layer of the 

 ; skin. In the snakes the scaly 

 fcache e afi,t f SStii covering is periodically shed. 



By the greater development of 



the neck the heart is carried back to a greater distance 



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