300 POPULAR HISTORY OF THE AQUARIUM. 



AVhen first deposited^ the egg is a little buffish-white ball 

 surrounded by a jelly-like envelope within which it moves 

 freely; in a few days it unrolls and gradually assumes a 

 tadpole form, still within its envelope. In this state may 

 be seen the simple rudiments of gills striking out at the 

 sides of the head. The front pair of these gills constitutes 

 holders by which the animal afterwards clings to objects, 

 and immediately behind the gills are little knobs which are 

 afterwards developed into anterior legs. Two bands of 

 brown spots are seen running down the back. It then 

 leaves the egg and swims about as merrily as most tad- 

 poles do, and while the anterior gills become more distinct 

 and useful as holders, the hinder ones become beautifully 

 branched. By degrees the fore legs are developed, and the 

 hinder ones appear at first in a very rudimentary form. A 

 fin-like keel extends along both edges of the tail and over 

 the back, and the transparency of the whole body is such 

 that the circulation can be seen in almost every part. After 

 the complete formation of gills, they begin to be gradually 

 absorbed, while the formation of true lungs is going on, 

 until at length, towards the end of autumn, it is an air- 

 breathing reptile, and no longer a fish. 



It is stated that the young Xewt, retiring from the water 



