SEA-TORTOISES. 171 



Large copper kettles to prepare the oil, and hundreds of red 

 earthenware jars, were scattered about on the sands. The com- 

 mandant commenced by taking down the names of all masters of 

 households, with the number of persons each intended to employ 

 in digging ; he then exacted from each a fine equal to fourpence 

 a head towards defraying the expense of the sentinels, when the 

 whole were allowed to go to the taboliero. It was exhausted by 

 the end of the second day, when each household had erected large 

 mounds of eggs beside their temporary hut. 



THALASSIANS, OR SEA TORTOISES. 



Cheloniadce, Gray ; Carettoidce, Fitzing ; Halyckelones, Kelgen ; 

 Oiocopodee, "Wagler. 



The Turtles or Sea Tortoises are distinguished from all others by 

 a comparatively flat carapace, long members, the extremities of 

 which terminate in broad paddles, the anterior much longer than 

 the posterior ones ; the toes, though formed of distinct pieces, can 

 only act together, thus constituting true oars, admirably arranged 

 for swimming. Their carapace, besides being flat, is indented and 

 elongated in front, and contracted behind, being disposed in such 

 a manner that the head and feet can be completely hidden. 



Marine Tortoises are the largest of their species : they swim 

 and dive with great facility, and can remain long under water. 

 The external orifice of the nasal canal is furnished with a sort of 

 valve, which the animal raises when it is in the air and closes when 

 under water ; but it rarely leaves its liquid element except in the 

 breeding season, when nature prompts it to seek the shore to lay its 

 eggs. Some of the species, however, seek the shore in the night, 

 when they frequent the banks of desert and solitary isles, where 

 they browse on marine plants. Although they walk with difficulty, 

 and even with pain, in quiet seas they may be seen floating like a 

 boat, in absolute immobility, and asleep on the surface of the 

 water. "With their horny jaws, which are hard and trenchant 

 as the beak of a bird of prey, some of them feed upon sea- weed 

 and algaB, while others feed on living animals, such as crustaceans, 

 zoophytes, and mollusks. 



We have seen how regularly and systematically the Land Tor- 



