234 THE DOCTRINE OF DESCENT. 



passing from the island of Bali to that of Lombocl<, 

 where the two regions are in closest proximity. In Bali 

 we have barbets, fruit thrushes, and woodpeckers ; on 

 passing over to Lombock these are seen no more, but 

 we have abundance of cockatoos, honeysuckers, and 

 brush-turkeys, which are equally unknown in Bali or in 

 any island further west. The strait is here fifteen miles 

 wide, so that we may pass in two hours from one great 

 division of the earth to another, differing as essentially 

 in their animal life as Europe does from America."^ It 

 we travel from Java or Borneo to Celebes or the Mo- 

 luccas, the difference is still more striking. In the first, 

 the forests abound in monkeys of many kinds, wild cats, 

 deer, civets and others, and numerous varieties of squirrels 

 are constantly met with. In the latter, none of these occur, 

 but the prehensile-tailed cuscus is almost the only ter- 

 restrial mammal seen, except wild pigs, which are found 

 in all the islands, and deer (which have probably been 

 recently introduced) in the Celebes and the Moluccas. The 

 birds which are most abundant in the Western islands 

 are woodpeckers, barbets, trogons, fruit-thrushes, and 

 leaf-thrushes ; they are seen daily, and form the great 

 ornithological features of the country. In the Eastern 

 islands these are absolutely unknown, honeysuckers and 

 small lories being the most common birds ; so that the 

 naturalist feels himself in a new world, and can hardly 

 realize that he has passed from the one region to the other 

 in a few days, without ever being out of sight of land. 



" The inference that we must draw from these facts 

 is undoubtedly that the whole of the islands eastwards, 



* This is too vaguely expressed. It would be nearer the mark to say, aj 

 Europe does from South America. (O. Schmidt.) 



