214 FROG TRIBE. 



upon marine plants and animals. In the breeding-season 

 they approach the shores, for the purpose of depositing 

 their eggs in holes, which, during the night, they scratch 

 in the sand ; and each female is said to produce more than 

 a hundred eggs in the season. In the course of twenty 

 or thirty days, according to the heat of the climate, the 

 young animals begin to crawl from under the sand. Tur- 

 tles are caught, principally, whilst asleep on the shore. 

 The seamen go gently to the place where they are to be 

 found, and successively turn them on their backs ; from 

 which position they are not able to recover their legs, 

 and are thus perfectly secured, until a sufficient number 

 has been caught. 



These animals have only two nails on each of the fore 

 feet, and one on each of the hind feet. Their shell is 

 nearly oval, somewhat broader behind than before. The 

 mouth is extremely large and wide. 



Imbricated Turtle. It is from this species that the 

 well-known substance called tortoise-shell, of which 

 combs and numerous ornamental articles are made, is 

 produced. Imbricated Turtles are found in the American 

 and the Asiatic seas, and are only considered valuable by 

 mankind on account of their shells. 



They are about two feet in length, and have two claws 

 on each of their feet, both before and behind. Their 

 shell is oval and depressed, the plates being loose, and 

 lying over each other. 



2. FROG TRIBE. 



These are nocturnal animals. They conceal them- 

 selves during the day, and issue forth only in the night. 

 Several of the species live in trees ; but the greater part 



