Height at withers about 25 inches. General colour pale fawn, rather variable in tone, sometimes tending towards brownish. Light lateral band very indistinct; dark band generally fawn like the back, occasionally darker, almost smoky brown. Central dark facial band deep rufous, a darker nasal patch often developing in old individuals. Light facial streak well defined, white. Pygal band almost obsolete, little or not darker than the back. Skull rather variable in the shapes of the nasal bones and premaxillæ. That of a male measures 6·55 inches in basal length, greatest breadth 3·1, muzzle to orbit 3·65. Horns of male, as well figured by Blanford under the name of _G. dorcas_, evenly diverging and curving backwards for four-fifths their length, their tips strongly bent inwards and upwards nearly or quite to a right angle. _Female._ Similar to the male, but the horns slender, scarcely ridged, their tips curved inwards rather than upwards; in length nearly equal to those of the male. _Hab._ Coast-lands of the Red Sea from Suakin to Massoua, and over the interior to Bogos, Barca, and Taka. It is possible that the Gazelles described and figured by Lichtenstein in the first part of his ‘Darstellung der Thiere’ as “_Antilope dorcas_,” which were stated to have been procured by Hemprich and Ehrenberg in Sennaar, may have belonged to the present species. Sundevall certainly considered them to be referable to a species distinct from the true _Gazella dorcas_, and proposed to call them “_isidis_,” from Lichtenstein’s vernacular name “Isis Antelope.” But this identification is by no means certain, and, at all events, the name “_isabella_,” under which this Gazelle was shortly diagnosed by the late Dr. Gray in 1846, will take precedence of Sundevall’s appellation. Gray’s description is very short, and does not allude to the shape of the horns, which are one of the most characteristic features of this species. His type specimen is still in the British Museum. It is an immature male, mounted, and stated to have been received from “Abyssinia,” though Gray in later papers gives “Egypt” and “Cordofan” as the localities for his _G. isabella_. Heuglin, in his various memoirs on the Antelopes of N.E. Africa, did not keep _G. isabella_ separate from _G. dorcas_, and united their localities. Sir Victor Brooke, in his monograph of the Gazelles, though he divides them and says that “amongst the smaller Gazelles no two species could produce two more dissimilar animals than typical specimens of _G. dorcas_ and _G. isabella_,” states his conviction that “every intermediate degree between them will be found represented in intermediate localities.” It is indeed true that _G. isabella_ is a very inconstant species and requires further careful study.