CHAPTER XIX 



TURTLES AND SNAKES 



Found In or Near Water 



Turtles 



Our native fresh water reptiles are nearly all turtles ( Testu- 

 dinata). The only snakes which stay consistently by the water 

 or in it are the brown water snakes which sun themselves 

 in shallow stream beds or rest on bushes overhanging the 

 water. 



There are many reptiles which live on land but relatively 

 few in the water, and even these aquatic ones have hardly 

 any structures or habits which are thoroughly distinctive of 

 water life. Reptiles are scaly, cold-blooded vertebrates like 

 the fishes, but fishes breathe by gills while reptiles have lungs 

 and generally use them. They do not transform as they 

 grow up like the gilled tadpoles which change to frogs. Newly 

 hatched turtles have lungs, breathe air, and look like their 

 parents. All of the fishes either lay their eggs or bring forth 

 their young in the water, and most amphibians lay their eggs 

 in it, but among the reptiles, even the turtles, which spend their 

 whole lives in the water, come out on land to lay their eggs. 



Turtles have an upper and a lower bony shell covered by 

 horny plates, the upper part being known as the carapace 

 and the lower one as the plastron. From the strongholds of 

 these shells turtles thrust out their heads, legs, and tails, 

 those with less shell, like the snapping turtle, having greater 

 freedom of action but less protection. A turtle's backbone 



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