XXVI 
DIV. I.- — VERTEBRATA, 
VERTEBRATA. 
CLASS III.— REPTILIA. 
Reptiles are divided into four sufficiently natural orders ; the 
Chelonian, Saurian, Ophidian, and Batrachian, severally represented 
by the Tortoise, the Lizard, the Serpent, and the Frog. The last 
of these is remarkable for presenting in early life a structure differ- 
ent from that which it is to assume when adult : thus the young 
tadpole, it is well known, breathes by gills, and in some genera of 
this order the gills are never lost. An easy transition is thus 
formed from the class Reptiles to the subsequent class Fish. 
Class. 
Reptilia 
Order. 
1. Chelonia ( Tortoise hind) 
2. Sauria ( Lizard hind) 
3. Ophidia {Serpent hind) 
4. Batrachia {Frog hind) 
ORDER I. — Chelonia. 
This order contains but one genus, the Linnaean genus Testudo, 
which has been divided into five subgenera, as follow. 
Genus. 
I. Testudo, L. 
Subgenus. Example of Species. 
1. Testudo, prop.'I 
Brong. (Land- > 
tortoises) ...... J 
2. Emys, Brong.'V 
(Fresh- water > 
tortoises) ) 
3. Chelonia, Brong. 'j 
(Sea-tortoises, or > 
turtles) J 
4. Chelys, Burner, 'j 
(Frog-mouthed > 
tortoises) J 
5. Trionyx, Geoff. \ 
(Soft tortoises) . . / 
T. graeca, L. Common tortoise 
Test, orbicularis, L. Speckled 
tortoise 
Test, mydas, L. Green turtle 
Test, fimbriata, Gm. Fimbri- 
ated tortoise 
Test, triunguis, Forsk. Soft 
tortoise of the Nile. 
