19 



regarding the flora of Sumatra that it is impossible to make any 

 estimate regarding the endemism of its flora. In regard to Java, 

 while its flora is relatively well known, the data in reference to 

 the geographic distribution of its constituent species, 

 approximating 5,000, is unfortunately not so arranged as to 

 be available. On account of the extermination of the virgin 

 forest over immense areas in Java it is very probable that its 

 endemism will be found to be appreciably lower than that of 

 other islands in Malaya. In the Philippines apparently about 

 60 per cent, of the known species are confined to the Archi- 

 pelago, but the percentage of endemic genera is distinctly smaller 

 than is that of Borneo. In the Malay Peninsula* the specific 

 endemism is apparently about 50 per cent. The endemism of 

 the Bornean flora is then not radically different from that of 

 the Malay Peninsula to the north-west or the Philippines to the 

 north-east, and it is suspected that the floras of Sumatra, 

 Celebes, and other large islands in Malaya will approximately 

 conform to this percentage of endemism. As our knowledge of 

 the Bornean flora increases it is almost certain that the 

 percentage of endemism will be found to increase rather than 

 to decrease as it seems to be apparent that more additions will 

 be made to the known Bornean flora in the form of species as 

 yet undescribed than in the discovery in Borneo of species 

 already characterized from extra-limital collections. This 

 expectation is based on the fact that the settled areas are much 

 better explored botanically than are the forested regions; and 

 it is a well established fact that in all parts of the Malayan 

 region, the percentage of endemism is high in the forested 

 regions and very low in the settled areas. Borneo presents in 

 addition to its strictly and dominantly Malayan elements certain 

 continental or boreal types; that is species otherwise known only 

 from Asia, chiefly the mountains of India, and an interesting 

 series of Australian types, but these Asiatic and Australian 

 types are relatively speaking few in number and are nowhere 

 dominant. 



In examining the list of Bornean species as to their 

 extra-Bornean distribution it is but natural that we find certain 

 ones which are known only from Borneo and from but one or 

 two of the surrounding regions. Thus lists could be compiled 

 of those species known only from Borneo and Java; Borneo and 

 Celebes; Borneo and Sumatra; Borneo and the Malay Peninsula; 

 Borneo and the Philippines, Borneo and Indo-China, but any 

 interpretations of such list must be strictly limited by our own 



* Estimate based on an examination of the families Caprifoliaceae to 

 Verbenaceae inclusive, as treated in King & Gamble's Materials 

 for a Flora of the Malayan Peninsula (reprint) 4 (1903-09) 

 1-916. 



