420 A DESCRIPTION OP 
SECTION II. ftactttan Reptile*. 
THE FROG. (Rana temporaria.) 
WHEN this reptile issues from the egg, in which it is pro- 
duced, it is merely a black, oval mass, with a slender tail. 
This tadpole, as it is called, is the embryo of the Frog, 
which, when it has attained a certain size, bursts its case, 
and appears with head and legs, leaving its tail with the 
rest of the exuviae of its former shape. This metamorpho- 
sis is one of the most curious in nature, and deserves our 
observation. The Frog, like other reptiles, needs not 
to breathe in order to put its blood into circulation, hav- 
ing a communication between the two ventricles of the 
heart. The common Frog lives during spring in ponds, 
