178 MAMMALS OF THE PACIFIC WORLD 



single species. Phalangers or possums are both common and 

 varied, while the characteristic tree kangaroos are found else- 

 where only on Great Kei Island and Cape York, Australia. The 

 New Guinea gazelle-faced wallabies (Dorcopsis) are a distinc- 

 tive group ; the island has also several distinct species of walla- 

 bies related closely to those of the continent. The feather-tailed 

 phalanger, the striped phalangers (also on Aru) and several 

 species of ring-tailed phalangers are typical of the Papuan 

 fauna. 



Close ties between southeastern New Guinea and northern 

 Australia are shown by the presence on the island of the sand 

 wallaby (Wallahia agilis), one of the short-nosed bandicoots 

 (Jsoodon), and dormouse phalangers. The common flying or 

 gliding possums (Petaurus) belong to distinct species in the 

 two subregions. Spinal-winged and tube-nosed bats, tree kanga- 

 roos, cuscuses, and mosaic-tailed rats represent New Guinea 

 types that have reached the continent. 



The Pacific islands north and east of the Australian Region, 

 as restricted here, are extremely poor in mammals. Pigs, house 

 rats, and mice have been carried to virtually all these islands 

 from the East Indies by various human migrants, in many cases 

 hundreds or thousands of years ago. Black rats, roof rats, and 

 Norway rats have been taken to the more important islands by 

 the vessels of white traders and explorers. These more aggres- 

 sive forms often have driven from the villages the Polynesian 

 rat, taken there much earlier by native travelers, and on some 

 islands may have caused its extinction. Bats have been carried 

 by storm, or have wandered, to many of the islands. 



The Micronesian Islands have one or two species of flying 

 foxes and a sheath-tailed insectivorous bat (Emballonura) in 

 addition to rats and mice. In the Carolines there is also a long- 

 tailed fruit bat (Notopteris), a primitive type known elsewhere 

 only from the New Hebrides, New Caledonia, and Fiji. No bats 

 are recorded from the Gilbert group, and only the sheath-tailed 



