34 FRESH WATER TORTOISES. ^ 



yellow, spotted with black, and about six inches long; it inhabits 

 Greece, Italy, France, and the large Islands of the Mediterranean. 

 In Italy, and Sicily, this species is eaten. 



20. THE FAMILY OF POND TORTOISES, (or Fresh Water Tor- 

 toises, Emys.) much more numerous than the preceding, forms 

 a sort of connecting link between the Land Tortoises, and those 

 that are essentially aquatic ; it is composed of Chelonians that 

 commonly live in marshes, and can swim, but yet differ very 

 little from the preceding in their organization. They are chiefly 

 distinguished by the conformation of their paws. The toes, five 

 in number, are distinct, moveable, furnished with hooked nails, 

 and united at their base by a palmate membrane of greater or 

 less extent ; but these characters are not always clearly marked. 



21. As in the Land Tortoises, the carapax is, in general, 

 entirely solid and oval in form ; but instead of being elevated, it 

 is more or less depressed. The neck is almost always longer 

 than in the preceding, and presents remarkable variations in its 

 conformation. In some, it is cylindrical, and surrounded by a 

 loose skin which permits it to be entirely drawn within, and at 

 the middle part of the carapax, while in others, it is a little 

 flattened, and covered by a close cutaneous sheath, which adheres 

 to the muscles, so that it can only be folded laterally on the body. 

 Almost all of them can conceal their paws between their shells, and 

 like the preceding, they have but four nails on the hind feet. 

 Their motions are^not as slow as those of the Land Tortoises, 

 and they swim with considerable facility. Their chief food con- 

 sists of fluviatile mollusks, batrachians, and annelides : they are 

 found on the margins of lakes, marshes, and rivulets, in which 

 the current is not rapid. 



22. The genus of Cistudes belongs to the division of fresh 

 water Tortoises, with a retractile neck : it is distinguished by the 

 sternum which is furnished with twelve plates, and divided into 

 two nearly equal parts, both moveable, and by the short tail. 

 The European Cistude, or Mud Tortoise, Tcstudo europceo, 

 has a depressed carapax, tolerably smooth, blackish with yellow 

 points, and about six inches long. It inhabits stagnant waters, 

 at the bottom of which it loves to keep buried in the mud. On 

 the approach of the cold season, it retires into holes, to hibernate. 

 It is found in the south of France ; but it is particularly common 



20. What are Pond Tortoises ? How are they distinguished from Land 

 Tortoises ? 



21. What are the characters of the Pond Tortoises? Where are they 

 found ? 



22. What are the characters of the European Cistude ? 



