344 MOSTLY MAMMALS 



in the world. Doubtless glad to be free from her charge, 

 the mother-toad thereupon rubs off what remains of the 

 cells against any convenient stone or plant-stem, and 

 comes out in all the glory of a brand-new skin, only, 

 before long, to undergo the whole process over again. 



The Surinam toad is, however, by no means the only 

 South American representative of its order whose nursery 

 arrangements are peculiar, a considerable number of frogs 

 and toads from the warmer regions of the New World 

 having ideas of their own as to the proper method of 

 bringing up a young family. Among these are certain 

 species nearly allied to the familiar tree-frogs of Europe, 

 but differing in that the females have a large pouch for 

 the reception of the eggs. Unlike the kangaroos and 

 other mammalian marsupials, in which the female has her 

 nursing-pouch on the under-side of the body, these mar- 

 supial frogs (Nototrema) have this receptacle placed on the 

 back, at the hinder end of which it forms a half-open 

 tunnel, with its aperture directed backwards, although the 

 pouch extends beneath the skin of the whole of the upper 

 surface of the body. In this capacious nursery are deposited 

 some fifteen or sixteen large eggs, which in due course 

 develop into complete little frogs, without living tadpoles 

 being produced, although at a certain stage the large eyes 

 and long tail of a veritable tadpole are visible through the 

 clear covering of the egg. 



According to a communication made by Dr. Goeldi, of 

 Rio de Janeiro, to the Zoological Society, the tree-frogs 

 of the genus Hyla inhabiting that part of Brazil show 

 considerable diversity in regard to nursing habits, although 

 none of them have any part of their own body modified 

 into a nursery. One species, for instance, builds nests of 

 mud on the shallow borders of pools, wherein the eggs 



