A BIG FOSSIL BONE. 79 



apteryx Is still the highest native animal, now 

 that the moa has been exterminated by man. 

 In like manner, the ostriches and rheas, the 

 cassowaries and emus, and all the other big 

 struthlous birds belong either to the Islands of 

 the Australian and Malay group, where they 

 have but little mammalian competition, and 

 that of a low grade, or to South Africa and 

 South America, both of which were long 

 equally insulated, and where most of the 

 fauna Is still of a very Inferior type. Similarly 

 with reptiles : the big saurlans are all dead 

 except in the case of the crocodiles and 

 alligators which haunt fresh waters alone ; 

 and fresh waters, we know, are almost as 

 insular In their way as islands themselves. 

 The Galapagos archipelago has for its highest 

 Inhabitant a monstrous lizard. Among am- 

 phibians, again, the gigantic salamander 

 belongs to Japan. 



On the other hand, the two great con- 

 tinents which developed the higher mam- 

 malian fauna — Europe and Asia in the east, 



