174 MAMMALS OF THE PACIFIC WORLD 



anoa may have reached Celebes by the same route or from the 

 Philippines. The presence on Mindoro of a dwarf buffalo, simi- 

 lar to the anoa, is not conclusive on this point, even if that 

 similarity is considered evidence of close relationship rather 

 than accidental convergence. The depths of the straits sepa- 

 rating Celebes from Borneo, the Lesser Sundas, and Philippines 

 are such that, considering also the faunal evidence, Celebes can- 

 not have been connected with any of these during the later 

 Tertiary. These straits were probably narrower than at pres- 

 ent during part of the Ice Age; lowering of the sea level six 

 hundred feet would reduce the width of the strait between south 

 Celebes and Borneo to twenty-five miles. Smaller mammals were 

 probably carried to Celebes from Borneo and other islands on 

 drifting masses of trees and vegetation, such as are frequently 

 torn loose by swollen rivers. The chances of survival under such 

 conditions are especially poor for larger mammals, but shrews, 

 rats, squirrels, several of which are closely related to Bornean 

 species, palm civets, and monkeys may have arrived in Celebes 

 in this way. The various degrees of differentiation shown by 

 the rats and squirrels, some of which are generically distinct, 

 some specifically, and some only racially, suggest that arrivals 

 took place through a great length of time. 



The only Australian element in Celebes consists of two species 

 of cuscus (Phalanger) , distinct from the several species of that 

 genus present in New Guinea. The spinal-winged fruit bat 

 (Dohsonia), although sometimes found as far west as Bali, is 

 characteristic of the Papuan Subregion, as is the tube-nosed 

 fruit bat (Nyctimene) and one of the long-tongued bats {Syco- 

 nycteris). Two genera of fruit bats are known only from Cele- 

 bes and its small associated islands. The lesser mosaic-tailed 

 rat (Melomys) is a member of a large genus of rats with head- 

 quarters in New Guinea. This genus is represented also on the 

 Talaut Islands between Celebes and the Philippines. 



Saleyer, Sanghir, and Talaut Islands have many of the mam- 

 mals found in Celebes. On the Sanghir group and Talaut are 



