1 82 ANIMAL BIOLOGY 



ceding and derives its name from its habit of making 

 long burrows in the sand. There are many species of 

 turtles in the ponds and streams of the United States. 

 One of the largest is the snapping turtle which sometimes 

 reaches a weight of forty pounds. It is named from its 

 habit of quickly snapping against an object of attack. 

 According to Dugmore the " amputation of a finger by a 

 medium-sized specimen, or a hand by a very large indi- 

 vidual would be an accomplishment of no difficulty to 

 the reptile." 



In the sea-turtles the limbs are in the form of flippers 

 adapted for swimming. The large leather-back turtle 

 of the Atlantic may reach a length of six feet and a weight 

 of a thousand pounds. The green turtle, and to a less 

 extent, the loggerhead, are much sought after for food. 

 The valuable tortoise shell of commerce is derived from 

 another large marine species, the hawk's-bill turtle, which 

 is widely distributed in the warmer seas. The eggs of 

 turtles and tortoises are oblong and encased in a calcareous 

 shell. They are usually buried in the sand near the water, 

 and are hatched by the warmth of the sun. 



