REPTILIA — TORTOISE. 687 



According lo the arrangement of reptiles by M. Brogniart, and followed 

 by M. Cuvier, founded upon their organization, and which is adopted in the 

 following summary, they are divided as noticed above, into four orders, viz. 

 Chelonian reptiles, or tortoises; Saurian reptiles, or lizards; Ophidian rep- 

 tiles, or serpents ; and Batrachian reptiles, or frogs. 



ORDER I. — CHELONIA. 



Reptiles of this order have a heart with two auricles ; body enveloped in 

 two plates or shields formed of the ribs and sternum ; four feet. 



THE TORTOISE. 



Tortoises are usually divided into those that live upon land, and those that 

 subsist in the water ; and use has made a distinction even in the name, the one 

 being called tortoises, the other turtles. However, Seba has proved that all 

 tortoises are amphibious ; that the land tortoise will live in the water, and 

 that the sea turtle can be fed upon land. A land tortoise was brought to 

 him, that was caught in one of the canals of Amsterdam, which he kept for 

 half a year in his house, where it lived very well contented in both elements. 

 When in the water, it remained with its head above the surface ; when 

 placed in the sun, it seemed delighted with its beams, and continued im- 

 moveable while it felt their warmth. The difference, therefore, in these 

 animals arises rather from their habits than their conformation ; and, upon 

 examination, there will be less variety found between them than between 

 birds that live upon land and those that swim upon the water. 



All tortoises, in their external form, much resemble each other ; their 

 outward covering being composed of two great shells, the one laid upon the 

 other, and only touching at the edges; however, when we come to look 

 closer, we shall find that the upper shell is composed of no less than thirteen 

 pieces. There. are two holes at either edge of this vaulted body; one for a 

 very small head, shoulders, and arms, to peep through; the other at the op- 

 posite edge, for the feet and the tail. These shells the animal is never 

 disengaged from; and they serve for its defence against every creature but 

 man. 



