POUCHED MAMMALS. 197 



by dark cross-bands. The banded-wallaby is a comparatively small species, 

 measuring only about 18 in. to the root of the tail. 



Still smaller are the rat-kangaroos, of Australia and Tasmania, of which 

 there are several distinct generic types, collectively constituting the sub- 

 family Potoroince. Of this group the distinctive characteristics are as 

 follows : In size all the forms are small, and may be compared to hares or 

 rabbits, the ears being usually small and rounded. In the fore-feet the 

 claws are greatly elongated, those of the three middle toes being dispro- 

 portionately larger than those of the other two ; as in the MacropodincR, 

 there are only four toes to the hind-foot ; and the long tail is hairy. In the 

 dentition the upper canines are invariably present and generally well- 

 developed ; the central pair of upper incisors have taller crowns than either 

 of the other two ; the fourth pre-molar, which is a compressed and trenchant 

 tooth of great antero-posterior length, may either be set in the same line as 

 the molars, or somewhat bent outwards in front ; and the molars, which 

 decrease in size from the first to the fourth, have tuberculated crowns. The 

 three species of typical rat-kangaroos forming the genus Potorous vary 

 somewhat in size, and have the nose naked, the ears very short and rounded, 

 the front claws long and somewhat slender, the hind-limbs nob very much 

 larger than the front ones, the hind-feet very short, with naked and coarsely- 

 granulated soles, and the tapering hairy tail devoid of a crest. In the 

 dentition the fourth pre-molar has from two to four vertical grooves. These 

 rat-kangaroos, which generally inhabit scrub-jungle, have their leaping 

 powers much less strongly developed than in the allied genera. In running, 

 both fore and hind limbs are brought into action. Nearly allied in external 

 character is the South Australian plain rat- kangaroo (Caloprymnus campestris), 

 which is an animal of comparatively large size, with the nose and ears as in 

 the typical genus, the front claws long and strong, the hind-feet relatively 

 long, with coarsely-granular soles, and the tail thin, cylindrical, and covered 

 evenly with short hair. While the last pre-molar is similar to that of the 

 preceding genus, the skull is generally like that of the next. The four species 

 of prehensile-tailed rat-kangaroos (Bettongia) are sufficiently distinguished 

 by the feature from which they take their popular name. The hair on 

 the tail is long, and forms a more or less distinct crest ; the last pre-molar 

 is much elongated, with from seven to fifteen distinctly-marked, oblique 

 grooves on the sides ; and the squared molars, of which the fourth is much 

 the smallest, carry four tubercles. These little animals are completely 

 terrestrial and nocturnal, using their prehensile tails solely for the purpose 

 of carrying bundles of grass and twigs to their nest ; such bundles being held 

 by the tail being bent down over and round them. Three of the species are 

 Australian, and the fourth Tasmanian. The last member of the sub-family 

 is the rufous rat-kangaroo (dEpyprymnus rufescens) of New South Wales, in 

 which the nose is partially hairy, the ears are somewhat elongated, the hind- 

 feet long, with narrow, granulated soles, and the tail evenly-haired. The 

 long and narrow last pre-molar has from seven to eight vertical grooves, but 

 no inner ledge ; and the molars are oblong, with the tubercles less distinct 

 and tending more to form ridges than in the other genera, while the decrease 

 in size from the first to the last is less marked. Like the other members of 

 the group, this animal is nocturnal, but it is remarkable for its speed and 

 the great length of its leaps when disturbed. 



Of especial interest is the tiny musk-kangaroo (Hypsiprymnodon moschatus) 

 of Northern Queensland, since it forms a connecting link between the 



