DIB A TAG 271 



Antelopes it forms, for instance, a mere wash of colour ; while in a 

 mounted example from near Omdurman presented to the British 

 Museum by Captain Dunn, it is deep rufous all over, and looks like 

 a saddle-cloth thrown over the back. In the latter specimen there is 

 also a faint streak of rufous on each thigh. Similar variations occur 

 with regard to the fore- legs. In the first of the two specimens 

 mentioned above there is a mere tinge of rufous on the front surface 

 below the knees, whereas in the second there is a more or less distinct 

 although narrow line of rufous. 



The colouring of this race of the dama is essentially the same as 

 that of the white oryx ; the only difference being that in the latter 

 chestnut patches are retained on the face, while the rufous saddle has 

 disappeared. Both are adaptations to a desert existence. 



It may be added that in the Sitznngs-Berichte Ges. I sis for 

 1906, p. 15, Mr. K. Heller gave the name of G. mhorr reducta to a 

 gazelle, represented by a menagerie specimen, stated to be inter- 

 mediate between dama typica and d. mhorr, but nearer to the latter, 

 from which it differs by the smaller horns, the brighter red and less 

 widely spread coloured area, the wholly white fore -legs, and the 

 nearly white head. The latter is fawn only at the back, and blackish 

 at the base of the horns. If this is really a distinct race, it should 

 be called G. dama redncta. 



THE DIBATAG OR CLARKE'S GAZELLE 



{Ammodorcas darkei) 



Dibatag, SOMALI 



(PLATE X, fig. 6) 



With the face-markings of a gazelle, 'the dibatag combines the 

 horns of a reedbuck, and is therefore entitled to rank as a genus by 

 itself, especially as the neck is longer than in the true gazelles, while 

 the tail is likewise relatively long and thin, and the limbs arc also 

 more elongated than in typical gazelles. This species was discovered 

 by Mr. W. H. Clarke in 1890, at the time the interior of Somaliland 

 was being opened up to European sportsmen, and was described 

 the following year by Mr. O. Thomas in the Zoological Society's 

 Proceedings (1891, p. 207). 



