LAND TORTOISES. 11 



terrestrial species are believed to subsist exclu- 

 sively on vegetable diet ; the marine species add 

 to this the flesh of large shelled mollusks ; the 

 marsh and fresh-water kinds prey on fishes, young 

 birds, insects, worms, and any other animals they 

 can overcome. 



About one hundred and twenty species are^ 

 known to belong to the Order, of which twenty- 

 eight are terrestrial, eighty-four are fluviatile, 

 and eight are marine. They are confined to the 

 warmer regions of the earth ; none of them being 

 properly inhabitants of the British Islands ; but 

 occasional occurrences of some of the marine spe- 

 cies on our shores are recorded, and a terrestrial 

 Tortoise is imported in some numbers from the 

 south of Europe, and kept as a pet in gardens. 



We shall consider the Tortoises as comprised in 

 five Families ; Testudinidce ^ EmydidcBy Triony- 

 cliidcE, SphargidcB, and Cheloniadce. 



Family I. Testudinid^. 



{Land Tortoises.) 



In this Family the carapace is very high and 

 convex, solid in structure, and covered with a 

 horny shell. The general form may be illustrated 

 by the common Greek Tortoise {Testudo GrcEca), 

 familiar to most of our readers. But the princi- 

 pal and most remarkable peculiarity, and that 

 which most perfectly indicates the manner of life 

 common to the group, is the conformation of the 

 limbs : the feet are short and stumpy, nearly of 

 equal length, with toes scarcely distinct, immov- 

 able,united by a thick skin, and forming a sort 



