CHAPTER XXXVII 



THE ORDER OF TORTOISES, TERRAPINS, AND TURTLES 



CHELONIA 



Surely there are few intelligent persons to 

 whom a live turtle does not appeal. From the 

 impregnable box tortoise to the grim alligator 

 terrapin, the giant tortoise of Galapagos, and the 

 marine monsters of the Gulf Stream, the diversity 

 in form and habit is very great. Fortunately, 

 however, a fixed knowledge of twelve species 

 will give a very good foundation on which to 

 build up this Order. 



SKELETON OF A FALSE GEOGRAPHIC TURTLE 

 (Graptemys pseudogeographicus.) 



P, plastron, 

 C, carapace, 

 Ra, radius, 

 Ul, ulna, 



Sc, scapula. 



Hu, humerua, 

 Tib, tibia. 

 Fib, fibula, 

 Fe, femur. 



General Characters. — A member of the Order 

 of Turtles is a reptile which has its skeleton on 

 the outside of its body, and its vital organs com- 

 pletely encased in a box of bone, called a shell. 

 The top half of the shell is called the car'apace, 

 and it is formed by the widening of the ribs until 

 they grow together and firmly unite wherever 

 their edges meet. The lower portion of the shell 



is called the plas'tron. The carapace of a male 

 tortoise is hollowed out underneath, but that of 

 the female is flat. The shell has an opening at 

 the front end to .receive the head, neck and fore- 

 legs, and the rear is open to afford space for the 

 hind legs and tail. The shell of a turtle is a city 

 of refuge, into which its owner withdraws its 

 head and feet whenever threatened by enemies. 

 In some species the shell is a remarkably perfect 

 means of defence. 



These reptiles have no teeth, but the edges of 

 their strong, horny jaws are sufficiently, sharp 

 and chisel-like to enable them to cut up vegetable 

 food. The head and neck move freely, in and 

 out. The skin is very tough and leathery. Like 

 other reptiles, the members of this Order repro- 

 duce by laying eggs and burying them, to be 

 hatched by the sun. Some of the large tortoises 

 live to the greatest age attained by any living 

 creatures now on the earth. 



In the original classification of the land-going 

 tortoises, and the water-loving turtles and ter- 

 rapins, it was an unfortunate mistake that the 

 name "tortoise" was not limited to the dry-land 

 species, "terrapin" to the hard-shelled species 

 inhabiting fresh water, and "turtle" to the spe- 

 cies with flippers which inhabit the sea. To-day 

 the names "tortoise " and "turtle " are applied so 

 indiscriminately through all three of the groups 

 mentioned, they are useless as distinctive titles 

 and the mixture is mischievously confusing. In 

 the interest of common sense I therefore propose 

 the following revised system of these common 

 names : 



1. All Chelonians of the land only shall 



be called Tortoises. 



2. All Chelonians of fresh-water shall 



be called Terrapins. 



3. All Chelonians of the sea to be 



called Turtles. 



To this at least one person will henceforth try 

 to adhere. 



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