REPTILIA 265 



lacertina) reaches a hundred and forty. The painted, or 

 "mud," turtles (A) are the commonest chelonians through- 

 out the country and may often be seen sunning themselves 

 on logs along swampy shores. The soft-shelled turtles 

 (PlatypeltiSj B) are remarkable for their leathery covering 

 and the extreme length of their necks. 



Through the middle states Blanding's turtle is common 

 along ponds and streams. It is a "semi-box" turtle; that 

 is, there is a hinge across the ventral part of the shell, so 

 that it may be closed over the retracted head and front 

 legs. It spends more time out of water than most turtles, 

 and is often found wandering in fields or woods. In the 

 southeastern states lives the terrapin, Terrapene Carolina 

 (E), which is a true box tortoise. It has the ventral plate 

 so hinged that it completely closes the shell. The terrapin 

 lives in woods and does not enter the water; feeding on 

 berries, earthworms, and insects. There are a number of 

 species of giant tortoises inhabiting islands of the Pacific 

 and Indian Oceans. They never enter the water, and feed 

 on cacti, grass, leaves, and fruits. 



Along the shores of warm seas the large marine turtles 

 are regularly caught for the market, being harpooned in the 

 open ocean or captured while ashore for breeding. The 

 loggerhead turtle may reach a length of four feet and weigh 

 five hundred pounds. The green turtle is somewhat 

 smaller (150 pounds), but is more highly esteemed for the 

 table. Almost any turtle is suitable as food for man, but 

 the marine turtles and tortoises are most generally used. 

 The Bureau of Fisheries has demonstrated by recent experi- 

 ments that the terrapin may 'be reared successfully for the 

 market on small farms. Most of the fresh-water turtles 

 do considerable damage by destroying fishes and small 

 aquatic animals which might serve as fish food. 



ORDER 4. CROCODILIA 



The crocodiles and their relatives resemble the lizards in 

 form, but attain a much greater size and are adapted to 



