224 NATURAL HISTORY OF THE [chap. ix. 



other groups are little known except to ornithologists. I 

 shall therefore refer chiefly to a few of the best known 

 and most remarkable families of birds, as a sample of the 

 conclusions furnished by the entire class. 



The birds of the Indo-Malay region have a close resem- 

 blance to those of India ; for though a very large proportion 

 of the species are quite distinct, there are only about fifteen 

 peculiar genera, and not a single family group confined to 

 the former district. If, however, we compare the islands 

 with the Burmese, Siamese, and Malayan countries, we 

 shall find still less difference, and shall be convinced that 

 all are closely united by the bond of a former union. In 

 such well-known families as the woodpeckers, parrots, 

 trogons, barbets, kingfishers, pigeons, and pheasants, we 

 find some identical species spreading over all India, and 

 as far as Java and Borneo, while a very large proportion 

 are common to Sumatra and the Malay peninsula. 



The force of these facts can only be appreciated when 

 we come to treat of the islands of the Austro-Malay 

 region, and show how similar barriers have entirely 

 prevented the passage of birds from one island to another, 

 so that out of at least three hundred and fifty land birds 

 inhabiting Java and Borneo, not more than ten have 

 passed eastward into Celebes. Yet the Straits of Macassar 

 are not nearly so wide as the Java sea, and at least a 

 hundred species are common to Borneo and Java. 



