brooks, and frequently wander freely over land from one pond to another. 



A few turtles are almost entirely terrestrial. The most widely distributed 

 of these are the box turtles, which spend most of their time searching among 

 and under leaves for choice insects and worms. Their shell pattern makes 

 them almost invisible against a background of fallen leaves, and their habits 

 of retiring completely into their shells and closing themselves into these "boxes'", 

 when disturbed, permit them to escape almost every enemy but forest fires. 

 Although they occasionally raid a strawberry patch, they do much good by de- 

 stroying insects. We have seen them gorged with Japanese beetles and have 

 found them to prefer hard-shelled beetles to soft grubs or worms. Captive 

 specimens usually take readily to bananas and meat scraps. The gopher turtle 

 is an extreme form which has become adapted to desert conditions and digs 

 deep burrows for itself . 



Sexual diiferences among turtles are not great. In several species the 

 male has a slightly concave plastron or lower shell, while the plastron of the 

 female is slightly convex. The male usually has a slightly longer tail and pro- 

 portionately longer claws than the female. In the common box turtle the male 

 has a reddish iris to the eye, while the iris of the female is yellowish or orange. 

 Mating usually takes place in the spring, soon after activity has been resumed. 

 By the early summer the females are ready for egg-laying, and often travel far 

 afield looking for suitable places in which to bury their leathery-shelled eggs. 

 Snappers, soft-shells, mud and musk turtles lay spherical eggs. Most of the 

 other groups lay ovoid eggs. These are left to develop by themselves and may 

 take from six weeks to several months to hatch, depending on the temperature. 

 It is thought that occasionally box turtles may pass the winter in the egg. The 

 young grow slowly, but have prospects of becoming centenarians. Up to eight 

 or ten years their age may be told with fair accuracy by the number of growth 

 layers around the margins of the scaly plates of the shell. After that age the 

 outer layer of these plates is shed periodically and only rough estimates are 

 possible. 



As in most of the cold-blooded vertebrates, turtles grow as long as they 

 live, but the rate of growth drops decidedly when they reach sexual maturity, 

 and continues to decline throughout life. Contrary to general impressions, 

 most species of turtles grow fairly rapidly under favorable conditions. In cap- 

 tivity turtles, like goldfish, are seldom given conditions favorable for anything 

 more than survival. Excluding the sea turtles, the largest members of the group 

 are the several species of giant tortoises found on the Galapagos Islands in 

 the Pacific Ocean and the Aldabra, Mauritius and Rodriquez Islands in the 

 Indian Ocean. The largest turtle found in the territory covered by this book 

 is the alligator snapper, attaining a carapace length of two feet and a weight 

 of over a hundred pounds. The second largest is the common snapper, which 

 may reach a carapace length of eighteen inches and a weight of fifty pounds. 



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