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Show 1867.] DR. J. E. GRAY ON AUSTRALASIAN RATS. 597 3. Notes on the Variegated or Yellow-tailed Rats of Australasia. By Dr. J. E . G R A Y , F.R.S., V.P.Z.S., F.L.S., &c. At the Meeting of this Society for May 8, 1866, I described a large Rat with a black and yellow tail from North Australia, under the name of Mus macropus*. W e have since received another specimen of this Rat from Cape York; and Mr. Gerard Krefft has informed m e in a note that it is evidently the animal which he has proposed to call Hapalotis caudimaculata in a paper on Australian auimals recently sent to this Society-)*. I may add to the former description that the cutting-teeth are bright orange-yellow in front; the front side of the upper one is broad, flat, and smooth, with a narrow, slightly shelving margin on the outer side of each tooth,-and of the lower one narrower, convex, with a single, subcentral, longitudinal, slightly impressed groove. The fur of this Rat is moderately soft, like that of Mus rattus, the longer hairs being rather rigid and bristle-like. The British Museum has lately received an adult and a young specimen of this Rat in spirits from Cape York. The feet of the young specimen are as white, and, in proportion to the size of the specimen, as thick and fleshy as those of the adult. The groove in the front of the lower cutting-teeth, the large size and pale colouring of the feet, and the nakedness of the scaly tail seem to indicate a peculiar section in the Rats, which may be called Gymnomys. In the description above quoted I observed that there were two other species of Rat in the British Museum, which had the tails more or less varied with yellow, and that one of them was from North Australia, but that it differed from M. macropus in having smaller feet. I might have added that it also differed from M. macropus from Cape York in being a spiny-furred Rat. This Rat also belongs to the section Gymnomys. It differs from M. macropus in the small size of the cutting-teeth and the feet, and there is also a difference in the colouring of the fur. It was brought from Menado, North Celebes, by Mr. Wallace in 1859. This specimen might at first be regarded as the young of M. macropus; but the size and colour of the feet, as well as the great difference in the fur, at once set at rest such a theory. The hair of the Celebes Rat is much softer and uniform in kind than that of the Rat from North Australia, which is much more rigid, with abundance of elongate black cylindrical hairs; and the shorter fur is made up of soft slender crisp hairs, intermixed with a number of very narrow, slender, linear, rigid, white, flat, channelled hairs. * P. Z. S. 1866, p. 221. t [See Mr. Krefft's paper, P. Z. S. 1867, p. 316. The same animal has been more recently described and figured by our Foreign Member Dr. W . Peters under the name Uromys macropus (Monatsb. Ac. Berlin, June 1867).-P. L. S.] / |