389 ISLAND LIFE part ii 



presenting a larger amount of speciality than the land 

 mammals ; for while a little less than three-fourths of the 

 birds are peculiar, only five-eighths of the mammals are 

 so ; and as physical isolation has certainly not been so 

 effective in the former group (the birds), we learn that 

 such isolation is not so important a factor in the pro- 

 duction of new species as it is usually supposed to be. 



The general character of the fauna of this group of 

 islands is evidently the result of their physical conditions 

 and geological history. The Philippines are almost sur- 

 rounded by deep sea, but are connected with Borneo by 

 means of two narrow submarine banks, on the northern of 

 which is situated Palawan, and on the southern the Sulu 

 Islands. Two small groups of Islands, the Bashees and 

 Babuyanes, have also afforded a partial connection with 

 the continent by way of Formosa. It is evident that the 

 Philippines once formed part of the great Malayan exten- 

 sion of Asia, but that they were separated considerably 

 earlier than Java ; and having been since greatly isolated 

 and much broken up by volcanic disturbances, their species 

 have for the most part become modified into distinct local 

 forms, representative species often occurring in the different 

 islands of the group. They have also received a few Chinese 

 types by the route already indicated, and a few Australian 

 forms owing to their proximity to the Moluccas. Their 

 comparative poverty in genera and species of the mammalia 

 is perhaps due to the fact that they have been subjected 

 to a great amount of submersion in recent times, greatly 

 reducing their area and causing the extinction of a con- 

 siderable -portion of their fauna. This is not a mere 

 hypothesis, but is supported by direct evidence ; for I am 

 informed by Mr. Everett, who has made extensive explora- 

 tions in the islands, that almost everywhere are found 

 large tracts of elevated coral-reefs, containing shells 

 similar to those living in the adjacent seas, an indisputable 

 proof of very recent elevation. 



Concluding Remarks on the Malay Islands. — This com- 

 pletes our sketch of the great Malay islands, the seat of 

 the typical Malayan fauna. It has been shown that the 

 peculiarities presented by the individual islands may be all 



