466 



ISLAND LIFE. 



[part it. 



comparatively narrow island, stretching from far south of 

 Tasmania to New Guinea ; while the crystalline and Secondary 

 formations of central North Australia probably indicate the 

 existence of one or more large islands in that direction. 



The eastern and the western islands — with which we are 

 now chiefly concerned — would then differ considerably in their 



MAP SHOWING THE PROBABLE CONDITION OF AUSTRALIA DUP.ING THE CRETACEOUS PERIOD. 



The white portions represent land ; the shaded parts sea. 

 The existing land of Australia is shown in outline. 



vegetation and animal life. The western and more ancient land 

 already possessed, in its main features, the peculiar Australian 

 flora, and also the ancestral forms of its strange marsupial 

 fauna, both of which it had probably received at some earlier 

 epoch by a temporary union with the Asiatic continent over 

 what is now the Java sea. Eastern Australia, on the other hand, 



