FOOD OF REPTILES. 119 



strong bony coverings, or shells, which afford a 

 sure protection against their natural enemies. 

 The upper part of these shells is composed of large 

 horny laminae, or plates, which are in some 

 species beautifully coloured. This, when sepa- 

 rated from the rest, is known under the name of 

 tortoise-shell, and is used for a variety of useful 

 and ornamental purposes ; as the making of combs, 

 boxes, watch-cases, and toys. 



The food of reptiles is very various. Serpents 

 live on small animals ; tortoises on sea weed, 

 called turtle-grass ; lizards and toads on insects 

 and worms. Nearly all of them are capable of 

 living for considerable periods without food. 

 The salamander will fast for several months, and 

 the tortoise for upwards of a year, and neither of 

 them appear to lose much bulk by their want of 

 food. The tenacity with which these cold-blooded 

 animals cling to life is also very remarkable ; they 

 often recover from the most dreadful injuries, and 

 sometimes even when a part of their body has 

 been destroyed, as a leg or a tail, it is reproduced 

 in the course of a few months. 



It is in warm climates that reptiles multiply most, 

 and arrive at an immense size, and that the poison 

 of the venomous kinds becomes most active and 

 pernicious. 



The obscure recesses inhabited by the majority 

 of the reptile tribes are far from being thoroughly 

 explored. How many of these still unknown 

 beings may lie concealed in the depths of inland 



