16 MAMMALS OF THE PACIFIC WORLD 



groups, those with only one pair of incisors or front teeth in 

 each side of the lower jaw (Diprotodontia) and those with 

 several lower incisors (Polyprotodontia). Kangaroos, phalan- 

 gers, honey possum, and wombats are diprotodonts ; bandicoots, 

 "native cats," "pouched mice," and banded anteaters are poly- 

 protodonts. But bandicoots are almost as closely related to 

 diprotodonts. 



In all animals of the diprotodont division and in the bandi- 

 coots of the polyprotodonts, the second and third toes of the 

 hind foot are very small and united. This strange condition, 

 which may serve as a combing device, gives the appearance of 

 a toe equipped with two claws. 



Not all marsupials are characterized by a pouch in the female 

 (the male never has a pouch), but most of them have this nurs- 

 ery bag in which to carry the young. In some types the pouch 

 opens backward. In males the scrotum is situated in front of 

 the penis. All marsupials and monotremes of both sexes have 

 a pair of bones projecting forward from the pelvis in the wall 

 of the abdomen. 



Newborn marsupials are tiny, hairless creatures with well- 

 developed hands. They find their way hand over hand through 

 the mother's fur into the pouch or to the region of the teats. 

 Each becomes attached by its mouth to a teat and the mother 

 pumps milk into it by contractions of the muscles covering the 

 milk glands, for it is too small to suck. 



Apart from a few American marsupials, common opossums 

 and their relatives, these animals are found today only in the 

 New Guinean-Australian region, with representatives on the is- 

 lands from Celebes and Timor to the Solomons. Ages ago, 

 during the days of dinosaurs, they were also widely distributed 

 in Europe. Many pouched animals in southern New Guinea are 

 so closely related to those on the Australian mainland that they 

 are considered only racially distinct. 



