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Show 1890.] MR. W. L. SCLATER ON SOME INDIAN MURID.E. 535 at its tip they reach a length of nearly half an inch ; the tail covered with square scales forming a series of rings which run to about 20 to an inch ; the tail is of a light brown colour above and below. In the hind foot (Plate X L V . fig. 8) the toes are very long, they form about ^ of the total length of the hind foot; the three middle digits are all equal in length and bear well-developed claws; the fifth digit is smaller and bears a very small claw that does not nearly reach beyond the pad ; the first digit is about the same length as the fifth, and is very much swollen transversely, it bears a flat nail as in Chiropodomys. The toe-pads are very large and swollen, so that the claws hardly extend beyond them; dorsally below the claw, they consist of two flat plates divided by a median groove; ventrally, they consist of the usual series of transverse plates, but much more developed than usual. The sole-pads are six in number; they are large and well-developed, and the proximal internal one very long and curved as in Rats. The digits of the fore feet (Plate X L V . fig. 9) are four in number; each bears a very small claw, which is almost embedded in the toe-pad ; the first digit forms a slight projection on the inner side of the haud, but has no trace of a nail; the toe-pads are swollen like those of the hind feet; the sole-pads are five in number as usual. The ears are very small and rounded ; the edge of the conch bears a fringe of long hairs all round, more than \ an inch in length; the short hairs inside the conch are white, outside brown. The mammae are 8 in number-two pairs of pectoral, two pairs abdominal. The skull (Plate X L V . fig. 7) has the same general appearance as that of Chiropodomys, being considerably shorter and wider than that of Mus ; the nasals and the anterior part of the skull are much shorter than in Mus; the interparietal is broader and more rounded in outline than in Chiropodomys ; the anterior wall of the antorbital foramen is perpendicular and does not project at all; below, the anterior palatine foramina are of moderate length, not markedly short as in Chiropodomys; they end some distance in front of the line of the anterior molars. The palate is somewhat narrower than that of Mus rufescens, and ends on a level with the line of the hind ends of the posterior molars, whereas in Mus rufescens the palate projects an appreciable distance further back ; the bulla is larger than that of Mus rufescens, and is not provided with the thickened anterior edge to the bony meatus which is found in Mus rattus. It is, however, the teeth which present the most distinctive characters. The incisors are quite smooth and have no trace of a groove or of any markings on them : the lower incisors are very broad, resembling those of Nesokia and much broader than in Mus; the anterior upper molar consists of three central, three external, and three internal cusps all arranged in a remarkably regular way, as will best be understood by reference to the drawing (Plate XLV. fig. 12). The cusps are all more or less equal to one another ; the second upper molar exactly resembles the anterior molar, but consists of six cusps only ; the posterior molar consists of one central, one |
