234 



FEOGS, TOADS, AN]) SALAMANDERS 





Fig. 163. — Eggs of frog. 



indistinct head and a wide tail. This form is known as a 

 "tadpole," or "polhwog." The tadpole lives in the water 

 attaclied, part of the time at least, to the jellylike mass 



or to water plants, by an 

 adhesive apparatus, or 

 " holder " on the head 

 near the mouth. A Httle 

 later, the tadpole becomes 

 a frec-swinmiing organism. 

 It 131-eathes by means of 

 small external gills on 

 each side of the heatl 

 (Fig. 164), and eats mi- 

 nute particles of A-egetable 

 matter found in the water. 

 Later, the external gills 

 disappear and are replaced 

 by intcrn.nl ones. After 

 some tiun', the hind leg.s 

 l>egin to appear and then 

 Ihe front legs, while, at the 



ici. r;,,i|H,i,.. iiigiiiv niagiiiiu.i, '^'1 1 1 !»' t liuc , tlic tall bccomes 

 (ind wiiowiiiiigiiis (,A). shorter and shorter. In 



