392 CLASS REPTILIA. 



Spirally, grow short and acquire the necessary infla- 

 tions for the stomach and the colon. The tadpole 

 accordingly lives only on aquatic plants, and the 

 adult animal on insects and other animal matters. 

 The limbs of the tadpoles are regenerated, almost 

 in a similar manner with those of salamanders. 



The time of these particular changes varies ac- 

 cording to the species. 



In temperate and cold climates, the perfect ani- 

 mal remains during winter under ground, or under 

 the water in the mud, and lives there without eating 

 and without respiration ; but during the fine season, 

 if it is hindered from respiring for some minutes, 

 by preventing it from closing the mouth, it pe- 

 rishes. 



The Frogs, properly so called, (Rana, Laur.), 

 have the body slender and the hind feet very long, 

 very strong, and more or less well palmated. Their 

 skin is smooth, their upper jaw is furnished all 

 around with a row of small fine teeth, and there is a 

 transverse interrupted range of them in the middle 

 of the palate. The males have on each side, under 

 the ear, a slender membrane which swells with air 

 when they cry. These animals swim and leap ex- 

 tremely well. 



Tlie Green Frog, {Rana Esculenta, L. Roesel. Ran. 

 pi. xiii. xiv.) 



Of a fine green, spotted with black. Three yellow 

 stripes on the back, the belly yellowish. 



