THE REPTILES 251 



standing in front of him, bob its head in and out in a most comical 

 salutation. During the summer months, when I did a great deal 

 of my literary work in the garden, the old tortoise would always 

 come up to greet me, and would stay by my chair as if pleased to 

 be near me. 



The River and Marsh Tortoises, with but one or two exceptions, 

 lead a land and water life. Their limbs are more slender than 

 in the Land Tortoises, and the carapace, as a rule, is flatter, but 

 it is bony and has a well-developed horny covering. To this group 

 belongs the Common Terrapin, or American Box Tortoise (Cistudo 

 Carolina), which has a very wide distribution in the United States 

 and in North America, from Maine to Florida, westward in Texas, 

 Iowa and Missouri, and in Mexico. It is carnivorous in its habits, 

 feeding upon insects, worms, and also some plants and fruits. The 

 Alligator Terrapin, or Snapping Turtle (Chelydra serpentina), has 

 a comparatively small buckler, but is provided with a plated head 

 armed with a hooked beak. It is an active swimmer and very 

 destructive among fish, for it is a most voracious reptile, greedily 

 devouring any animal substance that may come in its way. 



There are three genera of the Marine Chelonians, or Turtles, 

 the first (Chelonia) including the Edible Turtles, of which the 

 Green Turtle (Chelonia midas) is the type. They are free swimmers 

 in the great oceans within the tropics, liking deep water, but coming 

 on shore to deposit their eggs in the sand. Although very clumsy 

 and cumbersome on land, they swim easily and gracefully, even 

 the largest individuals, which may be 7 feet in length and weigh 

 800 or 900 lb., moving with remarkable agility through the water. 

 While the Green Turtle is always used at City banquets, the tor- 

 toiseshell of commerce is the product of the Hawk's-bill Turtle, 

 and is derived from thirteen overlapping bony shields on the cara- 

 pace. The Logger-headed Turtles are probably of more than 

 one kind ; their body is broad in front, and the marginal rim is 

 thin and broad behind. Geologically, the tortoises and turtles 

 are a very ancient order. 



The Nile Crocodile may be taken as the type of the order to 

 which it belongs. The long body is depressed and protected on 

 the back with solid keeled scales or " scutes." The limbs are 

 short and exceedingly powerful, and the toes are united, more 

 or less, by a web ; while the laterally compressed, crested tail is 



