454 ME. O. THOMAS ON MAMMALS F1IOM 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 II. 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, and 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 

 iuterdigital pits ; mamma3 two l . 



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 II. hylocrius. The following are, however, some of the differ- 

 ences observable : — The forehead where the horns rise is narrower 

 and with a much greater development of a supraorbital boss, almost 

 suggesting that of Capra ivalie, Biipp. ; 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 posteriorly, 

 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 mm. 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 

 II. jemlaicus again, rather than to those of //. 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 com- 

 parison 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 I/eruitrayus may be useful; all are from old 

 male specimens : — 



1 Males only examined. 



