208 The Under-Water World 



eggs are deposited. The parents then 

 quit the burrow, not by the way they 

 entered, but by a tunnel which they 

 construct after the eggs have been laid, 

 and which leads obliquely to the water. 

 By means of this exit the tadpoles,' when 

 the nest collapses, find their way by the 

 liquefaction of the froth to the pond 

 in which they complete their metamor- 

 phosis. The eggs, if taken from the nest 

 and put in water, die immediately. 



In an Australian toad the eggs are 

 laid in a dried-up pool, but do not hatch 

 until the rain has again filled the pool. 



In other tree frogs (Phyllomedusa and 

 Chiromantis) of South America, India 

 and tropical Africa, the eggs are attached 

 to the leaves of trees overhanging the 

 water. The larvae, after a few days, drop 

 into the pools below where they com- 

 plete their infancy. In certain other 

 tree frogs the spawn is deposited against 

 the walls of wells into which the larvae 



