236 



VERTEBRATA: BATRACHIA OR BATRACHIANS. 



changes before they acquire the form of the parents. 

 The name is from the Greek batrachos, a frog ; and the 

 group includes Frogs, Toads, Salamanders, Tritons, etc. 



Some kinds, as Tree-toads, lay their eggs on trees in places over- 

 hanging water, and the young, as soon as hatched, drop into the water. 



Pipa or Surinam Toad, of South America, lays its eggs in the water, 

 after which they are collected by the male, and placed on the back of 

 the female, the skin enlarging in such a manner as to inclose the eggs 

 in cells ; here the development goes on till the young come forth as 

 perfectly formed toads. 



A small frog of Venezuela has a pouch upon the back in which the 

 eggs are carried and hatched. 



FIG. 267. 



Blood-vessels of a Batrachian Frog in the Tadpole state, a, artery arising 

 from the single ventricle and dividing into six branches, which go to the three 



pairs of branchiae. 



FIG. 268. 



The same as Fig. 267, in the adult state. 



