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Show 454 MR. O. THOMAS ON MAMMALS FROM OMAN. [May 1, more like some of the larger Sheep, or even of the Musk Deer; quite unlike the soft fine hair of the Himalayan Thar; the fur over the greater part of the body is of medium length, shorter than in H. jemlaicus, longer than in H. hylocrius; but on the nape and middle line of the back anteriorly it is lengthened into a mane, while the hairs below the angles of the lower jaw, on the humeri, and on the femora are also elongated, so that at the knees and hocks there are formed more or less distinct ruffs. General colour pale sandy or brownish white, the dorsal mane broadly tipped with blackish brown. Face, cheeks below eyes, backs of ears, tail, aud a mark on each fetlock black or blackish, the relative prominence of the different markings as shown in the figure. Knees callous, naked; a bare glandular space on the chest; no interdigital pits ; mammas two \ The skull (fig. 2, p. 453) is in many respects a miniature of that of H. jemlaicus, to which it undoubtedly shows greater affinity than to that of H. hylocrius. The following are, however, some of the differences observable:-The forehead where the horns rise is narrower and with a much greater development of a supraorbital boss, almost suggesting that of Capra walie, Eiipp.; on the other hand, the bases of the horn-cores do not overhang the occipital region so much, so that the occipito-parietal plane, instead of pointing nearly horizontally backwards, slants up at an angle of about 45° ; this is also the case in H. hylocrius; the nasals are broader posteriori}', aud nearly fill up the prefrontal vacuities. The muzzle is longer and slenderer, and the nasal opening decidedly longer in proportion, this being apparently produced by a shortening of the nasals. The inferior wall of the orbit is less thickened externally. On the posterior part of the bony palate the nasal notch reaches further forward, some 4 m m . in front of the lateral notches, while in the allied species these latter are as much in front of the median one. The horns are in direction and general form similar to those of H. jemlaicus again, rather than to those of H. hylocrius, but they are longer in proportion, conspicuously slenderer, more evenly oval in section, and less rigid on the sides and less knotted in front. The horns of both specimens are much worn down, probably from a habit, shared, as Mr. Lydekker informs me, by many Thars, of rubbing the horns against trees or rocks. The differential characters here noted are drawn up on a comparison of an old male skull of the Thar with the typical, very aged, skull of the Arabian species, and some of them will no doubt in time prove to be due either to age or individual variation. The following skull and horn measurements (in millimetres) of the three species of Hemitragus may be useful; all are from old male specimens :- Males only examined. |