460 CIIELONIANS. 



FIRST FAMILY. Testudinina, (Lat. Tesludo, a tortoise.) 

 LAND TORTOISES. First Sub-Order, Amydse. 



The Tortoises of this family exhibit the greatest symmetry of 

 form, and are, on various accounts, entitled to the first rank in 

 the order. They are distinguished by their highly arched cara- 

 pace, and still more, by their short, clubby feet, terminating in 

 flat, spade-like nails. The outward armor is entirely ossified, 

 and harder and thicker, in proportion to the animal's size, than 

 in the Aquatic Tortoises. The shield is covered, externally, 

 with epidermal scales, and the skin everywhere more or less 

 protected with them ; on the most exposed parts, they are thick 

 and stiff, and form a continuous hard covering. The neck and 

 legs are short, and can be drawn entirely within the shell. 

 (See Radiated Tortoise on Chart.) 



The Land Tortoises show nothing of the fierce dispositions 

 exhibited by most of the other groups. never attacking or 

 making resistance, but resorting to the shield, and trusting to that 

 alone for protection. Their feet, which, in shape, have some 

 resemblance to those of the Elephant, are adapted to walking on 

 solid ground only ; when placed in water, these animals endeavor 

 to walk, as if upon land, having no swimming motion. Their 

 movement on dry ground is firmer and more steady, the weight 

 being almost equally supported by both pair of limbs ; and they 

 can travel for a distance at a pace less slow than any other Tor- 

 toises. The fore feet have, usually, five toes, and the hind ones, 

 four, which are furnished with short conical claws, well adapted 

 for digging. The food of the Land Tortoises is entirely vegeta- 

 ble. They appear most fond of the succulent stems of plants 

 and fleshy fruits. ''I have often," says Agassiz. "seen our 

 Gopher gnawing the stumps of cabbage, and apples falling from 

 the trees in my garden, as the Squirrels do, holding them between 

 their feet," The lungs are very much larger in the Land Tor- 

 toises than in any other family of the first sub-order. Their 

 size is also, on the whole, larger than that of any other family 

 of that division. 



The Land Tortoises include four genera. 



(1) tCinixys, of which there are two or three species found in 

 Guiana. In thes'e, the hind part of the carapace is not united to 

 the front part, and is movable, so that the animals can shut in 

 their hind limbs and tail. 



(2) Pyxis. (Gr. puxis. a box.) This genera includes the 

 Land Box Tortoises, having the front part of the plastron mova- 



