RAT-KANGAROOS. 249 



Banded Wailab (Lagostrophus fasciatus), of Western 



' Australia, which is about the size of a hare, and is easily recognised 

 by the dark transverse bands crossing the hind-quarters, forms the single re- 

 presentative of a genus. It is specially characterised by the presence of long 

 bristly hairs on the hind-feet, which completely conceal the claws. The muzzle 

 is naked; and the ears are small and rounded. The skull is characterised by 

 its narrow muzzle, and inflated auditory bulla ; while there is no tusk, the two 

 series of upper incisor teeth meet in an angle, and the two halves of the lower 

 jaw are welded together at their, union. These pretty little wallabies inhabit the 

 scrub-jungle and the margins of swamps on the west coast of Australia and the 

 small adjacent islands. On the islands they form tunnels beneath the dense bushes 

 by gnawing off the lower branches on certain lines ; and they can only be beaten 

 out from their cover by the aid of dogs. On the mainland they are said to skulk 

 in the open like hares. 



The whole of the members of the family hitherto considered 



. ** 



form a single subfamily primarily characterised by the circumstance 

 that the three incisor teeth of the upper jaw are of nearly equal height, while the 

 tusk, or canine tooth, if present at all, is very minute. We now come to a second 

 group or subfamily, including a number of small forms known as rat-kangaroos 

 or potoroos, which differ in many important respects from the preceding. These 

 creatures, none of which are larger than an ordinary rabbit, are characterised by 

 having the first incisor tooth on each side of the upper jaw (as shown in the figures 

 on pp. 237 and 239) considerably taller than either of the others, and narrow and 

 curved in form ; while there is always a rather large and blunted upper tusk. 

 Then, again, whereas in the preceding subfamily, with the exception of Mtiller's 

 kangaroo and its allies, the permanent premolar tooth is comparatively short from 

 front to back, in the group under consideration the same tooth, as shown in the 

 aforesaid figures, is much elongated in this direction, and has a straight cutting- 

 edge, and its two surfaces generally marked by vertical grooves and ridges. 

 Sometimes, moreover, the same tooth may be bent slightly outwards, instead of 

 forming a continuation of the line of the molars. The latter have blunt tubercles 

 at their four angles, instead of complete transverse ridges; and the last of the 

 series is, instead of being larger, always smaller than the one in front of it. The 

 rat-kangaroos are further distinguished by their narrow fore-feet, in which the 

 three middle toes are much longer than the other two, with long, narrow, and 

 slightly-curved claws ; whereas in the broader front paws of the preceding group, 

 the whole five toes are nearly equal in length, and have highly-curved claws. All 

 the rat-kangaroos have small rounded ears, and long furry tails, of which the 

 extremities are partially prehensile in some of the species. Externally, the rat- 

 kangaroos cannot well be distinguished in general appearance from some of the 

 smaller short-eared representatives of the preceding group ; and it is accordingly 

 of prime importance that the foregoing distinctive characteristics should be 

 thoroughly understood. The group comprises nine species, which are confined to 

 Australia and Tasmania, and are divided into four genera. 



Common Rat- The common rat-kangaroo (Potorous tridactylus), that figured in 



Kangaroo. the illustration on the following page, may be taken as our representa- 



