Hind legs below the hocks nearly white, except for a longitudinal black stripe on the front of the cannon-bone. Fore legs white below knee, with a black spot or stripe on the front of the cannon-bone; above the knee on the outer and inner side the leg is black almost up to the shoulder, but on the inner side it is sometimes white above, the white area extending for a short distance on to the front of the leg at its base. Horns nearly straight, rarely attaining a length of about 47 inches, more commonly less than 40. A skull has the following dimensions:—Basal length 14·5 inches, eye to nose 10, greatest width 6·25. _Female_ similar to the male, but slighter, with longer and more slender horns, which are less distinctly ringed and sometimes slightly bent. _Hab._ Arid deserts of South-west Africa, from Bechuanaland north to Mossamedes. The Dutch colonists who settled at the Cape in the course of the seventeenth century named the principal Antelopes which they met with there after the animals in Europe that they supposed to be their closest allies, or to be most nearly similar to them, but in many cases very inappropriately. Thus the “Eland” received its name from the Elk (_Alces machlis_), the “Reh-bok” from the Roe (_Capreolus caprœa_), and the present Antelope from the Chamois or Gemse of the Alps (_Rupicapra tragus_), although in all these cases it is difficult to discern much resemblance between the European species and the South-African animals which were called after them. Nevertheless the term “Gemsbok” has stuck to the Oryx of the Cape, and is still a familiar name for this beautiful Antelope both among the Dutch and the English in South Africa. As we have already shown, it is the type, or at any rate the first species, of de Blainville’s genus _Oryx_, and that must be its generic name, but to decide what term should be selected as its proper specific name is by no means an easy task.