AMPHIBIOUS VERTEBRATES. 20 1 



FIG. 243. Metamorphosis of the frog, e, eggs ; i, tadpoles just out of the 

 egg ; 2, with outs.de gills ; 3, with gills hidden, and beak-like mouth ; 4, 

 hind-legs appearing ; 5, all legs grown, but fish-tail remaining ; 6, put- 

 ting on frog appearance, tail being absorbed ; 7, young perfect frog. 



Toads (ufonict<z). The toads in the adult form are 

 terrestrial, the toes are webbed, and the skin generally 

 covered with warty protuberances. The eggs of Pelobates 

 are deposited in the water in a loop. The male of the 

 Alytes of Europe winds the eggs about its body in strings, 

 and goes into the water, remaining until the young appear. 

 The spade-foot is noted for its sudden appearance in cer- 

 tain localities* It remains but a day or so in the water, 



