224 
MACKOPODID/F.. 
The species of the present section have the body more com¬ 
pact, the hinder legs shorter, and the head much more elon¬ 
gated and pointed than the Bettougias; the molar teeth are 
proportionately smaller, and the anterior pair of incisors of 
the upper jaw are longer, descending much below the level 
of the other incisors. To these principal points of distinction 
between the Bettongias and the Potoroos, we may perhaps 
hereafter have to add the “anchylosed and unanchylosed 
condition of the tibia and fibula : having seen but the 
skeleton of one species in each, I am not aware, however, 
whether such a difference is constant. In a skeleton of Betton- 
gia, which I feel no doubt is referable to the B. Gahnardii , 
contained in the Museum of the Royal College of Surgeons, 
the bones in question are anchylosed at their lower extremity, 
whilst in more than one skeleton of the 11. murium, I have 
found the tibia and fibula distinct throughout. 
HYPSIPRYMNUS {Potatoits) MURINUS, 
Rat-Tailed Hypsiprymnus, or Rat-Kangaroo. 
Poto Roo t or Kangaroo-Itat. White's Journal of a Voyage to New South 
Wales, p. 286, and PI. . 1790. 
Macropus minor . Shaw, General Zoology, vol. i. Part 2, p. 513, PI. 116. 
1800. 
Hypsiprymnus murinus. Illigf.r, Prod. Syst. Mamm. p. 79. 1811. 
Potorous murinus. Df.sm. Nouv. Diet. d’ l list. Nat. tom. xxviii. p. 79—SO, 
Mammalogie, Part 1, p. 271. 
Hypsiprymnus setosus. Ogilbv, Proceedings of the Zoological Society for 
November, 1831, Part 1, p. 119. 
u Peron. Quor et Gaimard, Zool. de l’Uranie, p. 64. 
Bet tony of the natives of New South Wales. Mus. Lin. Soc. 
? myosurus. Ogilby, Proc. Zool. Soc. for May, 1835, Part 6, 
p. 62. 
Fur long, loose, slightly glossy, and rather harsh to the touch: 
general colour, dusky brown ; the upper parts of the body much 
