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Show 610 MR. W. L. SCLATER ON A NEW JERBOA. [Nov. 4, 6. On a new Genus and Species of Rodents of the Family Dipodidce from Central Asia. By W . L. SCLATER, M.A., F.Z.S. [Eeceived October 25, 1890.] (Plate L.) While engaged in examining and cataloguing the collection of Mammals in the Indian Museum, Calcutta, I came across two specimens which seemed to belong to a species of the genus Alactaga. On removing the skull from one of the specimens, I found that I was quite unable to identify it with any species of Alactaga hitherto described. Nor have I, in the course of fresh researches, been able to find any specimens, either in the Indian or the British Museums, which in any way resemble it. In fact the skull in question differs so strikingly from that of all the other forms of Dipodidce, that it seems necessary to make a new genus for its reception. I therefore propose the generic name Euchoreutes (ev bene et -^opevrns saltator) for this Rodent, with the specific term naso, on account of its prominent and pig-like snout. EUCHOREUTES NASO, sp. nov. (Plate L.) The fur is soft and long, of a blackish-grey colour, mixed with red on the back ; posteriorly the red predominates and becomes much more conspicuous at the root of the tail ; the sides and belly are pure white, quite sharply defined from the grey colour of the back ; the snout, cheeks, and chin are also white. The snout is very projecting and pig-like, and there is a large bare area round the nostrils, which is surrounded by a ring of very short stiff upright hairs. In Alactaga indica the snout is much shorter and more rounded, and there is no bare area round the nostrils. The ears are very long, and extend considerably beyond the end of the snout when pressed forward ; they are clothed within with fine scanty silver hairs ; externally, where they are divided into an anterior and posterior portion by a fold, the anterior part is covered with a few silvery hairs, while the posterior is hairless. There are four pairs of m a m m a ? - one pair of pectoral, one pair of inguinal, and two pairs intermediate. In the anterior limb the digits and claws are very long and slender ; all the five digits are distinctly clawed, whereas in Alactaga indica the first digit bears a nail. There are four carpal pads, two smaller distal pads at the base of the fourth and fifth digits, and two larger subequal proximal pads. In the hind limb, which is rather long, the first and fifth toes are subequal, the first being slightly longer ; the ends of the claws do not quite reach the metatarsal joints of the three median digits. The second, third, and fourth toes are subequal, the median one being only very slightly longer than the other two; the difference |