362 MOSTLY MAMMALS 
to excite our unbounded wonder and admiration. But in 
many frogs and toads the course of development is modified 
in various ways from this typical plan in accordance with 
the special needs of their existence, thus giving rise to 
many wholly unexpected phenomena and peculiarities. 
The first peculiarity is displayed by the Japanese frog 
(Rhacophorus schlegelt), in which the eggs are laid in the 
muddy banks of paddy-fields or ponds above the water- 
level. The egg-mass is kneaded into a froth by the legs 
of the female parent, and its exterior hardens into a kind 
of crust. Within this ‘‘ pudding” the tadpoles are hatched ; 
and eventually the mass breaks up into a fluid, and bursts 
its crust to flow into the water, carrying with it the tad- 
poles. If the eggs be removed from the “ pudding” and 
transferred to water, they immediately perish. 
In a West African frog (Chiromantis guineensis), as well 
as ina Brazilian species (Phyllomedusa theringt), the eggs, 
on the other hand, are deposited in nests formed of leaves 
glued together by the parent. And in both instances the 
tadpoles swim about within a frothy substance. In the 
case of the latter species the nest has an opening below 
through which the tadpoles are eventually discharged into 
the,,water over which it is built; but those of the first 
species are believed to be washed off the leaves by rain, 
falling into water below. 
The female of the little Paraguay tree-frog (Phyllomedusa 
hypochondrialis) carries her partner on her back until a 
suitable leaf in the neighbourhood of water is found, when 
the two parents bend back its tip in such a manner as 
to form a funnel, in which the female deposits her spawn. 
Two nests of this description, each containing about one 
hundred eggs, may be formed by each pair of frogs. 
After an interval of six days the tadpoles hatch out and 
