ii4 MOSTLY MAMMALS 



Borneo, Java, Celebes, and Mindanao, together with some 

 of the neighbouring islets, and are totally unknown to the 

 eastward of the Molucca Sea. Although, being arboreal 

 animals, it may be argued that, like the cuscuses of Celebes, 

 they may have been carried about by floating timber, yet 

 it seems in the highest degree unlikely they should have 

 reached all the islands with an Oriental type of fauna and 

 avoided all those where the true Australian type comes 

 in. Moreover, they are very delicate animals, exceedingly 

 difficult to keep alive in captivity, and there is accordingly 

 a strong probability that they are native to the islands 

 where they occur. Like so many of its other animals, the 

 tarsier of Celebes is black as, indeed, are the species 

 from the other islands. 



So far, then, as their mammals are concerned, it seems 

 probable that at no very distant epoch Celebes, Borneo, 

 and the Philippines formed one land area; while Borneo 

 itself was connected with the mainland, probably by way 

 of Sumatra, the orang and some other species being common 

 to these two islands and unknown elsewhere. It is further 

 probable that Celebes, and most likely a portion of the 

 Philippines, became isolated before Borneo ceased to be 

 connected with Sumatra or at all events with the main- 

 land. Possibly this early separation may account for a 

 very curious difference between the fresh-water fishes of 

 the two areas; Celebes having no carps (Cyprinidae) or 

 cat-fishes (Siluridae), both of which are abundant in Borneo, 

 as in Asia generally. With regard to the south-western 

 portion of the Philippine group, it is important to notice 

 that the island of Palawan shows evidence of a closer con- 

 nection with Borneo than with the rest of the archipelago 

 to which it belongs. On the other hand, the mountains 

 of Luzon, in the Northern Philippines, are the home of 



