(1) <i>Potorous</i>, (2) <i>Caloprymnus</i>, (3) <i>Bettongia</i>, (4) <i>AEpyprymnus</i>.

(1) The first genus (<i>Potorous</i>, q.v.) includes animals about the size of a large rat; according to Gould, although they stand much on their hind-legs they run in a totally different way to the kangaroo, using fore and hind-legs in a kind of gallop and never attempting to kick with the hind-feet. The aboriginal name was <i>Potoroo</i>. The species are three—the Broad-faced Kangaroo-Rat, <i>Potorous platyops</i>, Gould; Gilbert's, <i>P. gilberti</i>, Gould; Common, <i>P. tridactylus</i>, Kerr. They are confined to Australia and Tasmania, and one Tasmanian variety of the last species is bigger than the mainland form. There is also a dwarf Tasmanian variety of the same species.

(2) A second genus (<i>Caloprymnus</i>, q.v.) includes the <i>Plain Kangaroo-Rat</i>; it has only one species, <i>C. campestris</i>, Gould, confined to South Australia. The epithet plain refers to its inhabiting plains.

(3) A third genus (<i>Bettongia</i>, q.v.) includes the Prehensile-tailed Rat-Kangaroos and has four species, distributed in Australia and Tasmania—

Brush-tailed Kangaroo-Rat—
<i>Bettongia penicillata</i>, Gray.

Gaimard's K.-R.—
<i>B. gaimardi</i>, Desm.

Lesueur's K.-R.—
<i>B. lesueuri</i>, Quoy and Gaim.

Tasmanian K.-R.—
<i>B. cuniculus</i>, Ogilby.

(4) A fourth genus (<i>AEpyprymnus</i>, q.v.) includes the Rufous Kangaroo-Rat. It has one species, <i>AE. rufescens</i>, Grey. It is the largest of the Kangaroo-Rats and is distinguished by its ruddy colour, black-backed ears, and hairy nose.

[Mr. Lydekker proposes to call the animal the <i>Rat- Kangaroo</i> (see quotation, 1894), but the name <i>Kangaroo- Rat</i> is now so well-established that it does not seem possible to supersede it by the, perhaps, more correct name of <i>Rat-Kangaroo</i>. The introduction of the word <i>Kangaroo</i> prevents any possibility of confusion between this animal and the true rodent, and it would seem to be a matter of indifference as to which word precedes or follows the other.]