THE PREHENSILE-TAILED RAT-KANGAROO. 67 
tail thinly covered with pale yellowish hairs, closest on the 
under side of the tip; centre of chest naked and glandular. 
Length of head and body about 18 inches; of tail 14 inches. 
Distribution.—South Australia, 
THE PREHENSILE-TAILED RAT-KANGAROOS. 
GENUS BETTONGIA. 
Bettongia, Gray, Mag. Nat. Hist., vol. i., p. 584 (1837). 
Nose wholly naked; ears very short and rounded; fore 
claws long and strong; hind feet longer than head, with the 
naked soles coarsely granulated ; tail more or less prehensile, 
thickly haired, with a more or less distinctly marked crest. 
Last premolar tooth long and stout, with from seven to fifteen 
distinct oblique grooves ; molars squared, with four tubercles, 
_the last of the series much the smallest of the four. 
Externally the four species of this genus are remarkably 
similar,—so much so that it is difficult to distinguish them by 
appearance alone. There are, however, very well-marked points 
of difference in the skulls and teeth. These creatures are the 
only ground-dwelling Mammals with prehensile tails ; the latter 
| being used to carry bunches of grasses and sticks, which are 
held by the tail being bent down over and round them. 
| I. LESUEUR’S RAT-KANGAROO. BETTONGIA LESUEURI. 
| 
| Lypsiprymnus lesueuri, Quoy and Gaimard, Voyage Uranie, 
Zool., p. 64 (1824). 
_Aypsiprymnus grayt, Gould, Proc. Zool. Soc., 1840, p. 178. 
| Bettongia grayt, Gray, in Grey’s Australia, Appendix, vol. ii., 
| Pp. 403 (1841). 
Perameles harveyi, Waterhouse, Proc. Zool. Soc., 1842, p. 47. 
(1888). 
