98 THE WANDERINGS OF ANIMALS [OH. 



No Hylidae exist in Africa and Madagascar nor India 

 and the Malay Islands, but there are plenty in Aus- 

 tralia. The same principle, suggestive of a former 

 antarctic connexion, is followed by the Cystigna- 

 thidae, which are plentiful in South and Central 

 America (a few in the U.S.A.) and Australia, and the 

 solitary Liopelma in New Zealand. 



The opposite principle of dispersal applies to the 

 Ramdae or typical frogs. The greatest number of 

 their many genera with near 300 species occurs in 

 Africa and the Indo-Malayan countries. All the 

 numerous species of the whole of North America 

 and Eurasia belong to the genus Rana, except the 

 closely allied arborealised Rhacopliorm which ranges 

 from Japan through India and Malaya ('flying frog') 

 to Madagascar. Rana itself, with about 150 species, 

 has nearly the same range as the family, and, what is 

 most significant, a few species have reached north- 

 west South America, but not the Antilles ; it occurs 

 also in Madagascar, New Guinea, Northern Australia 

 and the Solomon Islands. Thus the frogs, toads and 

 tree-frogs still proclaim the fundamental divisions of 

 the Old South and North World. 



CROCODILES. 



Crocodiles in a wide sense are known from the 

 Lower Jurassic epoch and they developed an abun- 

 dance of marine and freshwater groups all over the 



