Page:Encyclopædia Britannica, Ninth Edition, v. 2.djvu/115

Rh consists in the peculiar and characteristic type of structure of the horns. These appendages are essentially processes of the frontal or forehead bone of the skull, and so far from being deciduous, that is, being shed at stated periods, as in the deer, the horns in the Cavicornia are permanent and persistent throughout life. The process arising from the frontal bone constitutes the inner shaft, or " core " of the horn ; and this bony core is covered by a horny sheath. The horny sheath is purely epidermic in its origin and nature ; that is, it consists of a special development of the outer skin or epidermal tissue. When these structures are contrasted with the horns of the deer, with which group, it may be remarked, the antelopes are frequently confused, but from which they are essentially distinct, they are at once seen to be different in every particular. The horns or " antlers " of the deer are solid, and consist entirely of bony tissue ; and they are, furthermore, shed annually. The antelopes, with the other Cavicornia, participate in the following characters, in addition to those furnished by the structure of the horns. Both sexes are generally pro vided with horns. The dental formula or arrangement of the teeth exhibits a want of incisor teeth in the upper, and six incisors in the lower jaw ; canines totally wanting in the upper jaw, and two in the lower jaw ; and twelve molars in each jaw. The dental formula, therefore, runs thus:— 3-3 1-1 PM. 3-3 M - !-* The feet are cleft ; and accessory or supplemental hoofs exist on the back aspect of the feet. The antelope family (Antilopidce), including a great number of different species, is generally distinguished from the allied families of the sheep, oxen, and goats, by the light, graceful, and deer-like form of its members. The horns are chiefly cylindrical in shape, but may be twisted in an annular or spiral manner. The beard, or " dew-lap," characteristic of the deer tribe, is generally absent in the antelopes ; and of all the Cavicornia, they constitute the only family in which the curious " tear-pits " or " lachrymal sinuses " of the eyes are found. These latter organs are small sacs situated below the eyes, and devoted to the secretion of a yellow substance of a sebaceous or waxy nature. As regards their distribution, the antelopes are chiefly found in the eastern hemisphere, and Africa appears to be the great centre of distribution of the group. South Africa is especially rich in antelopes, and they may be regarded ns representing in that continent the deer of other regions of the world. In habits they are, for the most part, gregarious, and are frequently found in immense herds inhabiting the grassy plateaus and plains ; whilst some species are exclusively mountainous in their distribution. The particular form to which the name of " antelope " has been generally assigned is the Antilope cervicapra (Plate I. fig. 5), found in the East, and distinguished by the triple curve of its annulated horns. The gazelle or Barbary ante lope (Gazella Dorcas) has long been famed in the poetic imagery of Eastern writers. It has two small black horns. The algazel (Gazella Leucoryx) (Plate I. fig. 2), found in Persia and Arabia, has slender limbs, and the horns of the male are horizontal, bent backwards, obliquely annulated, with smooth tips, and nearly three feet long. Several nearly allied species inhabit the northern portions of Africa, the Gazella Corinna (Plate I. fig. 3) exemplifying one of these latter forms. The springbok (Gazella Euchore) of the Dutch settlers, or "springer" antelope, is a well-known 1 n-m inhabiting the southern districts of Africa. The horns are simple and annulate, and are curved, so as to form a lyrate or lyre-shaped figure. This animal s activity and powers of leaping have procured for it its familiar names; and travellers have long noted the immense numbers of these forms which congregate in vast herds in the plains of Southern and Central Africa. The bontebok (Gazella Pygarga), and the blesbok (Gazella albifrons), are allied to the springbok, and inhabit the same regions as that form. The other species found in Southern Africa include the rarer blue antelope (Gazella leucoplioea), and the roan ante lope (Gazella equina), a large species described by Burchell. The water bok (Kobus ellipsiprymnus) (Plate I. fig. 4), a well-known African form, is of considerable size. Its familiar name has been derived from its habit of frequent ing rivers, and from its powers of swimming. The horns are large, curved, and spreading. The klippspringer (Oreo- tragus saltatrix) of South Africa has a close resem blance in size and habits to the European chamois. The koodoo (Strepsiceros Koodoo) (Plate I. fig. 1), inhabiting South and West Africa, and otherwise widely distributed over the continent, is provided with very long spiral horns, which, however, exist only in the male animals. These latter antelopes represent " solitary " species, that is, they are generally found living in detached pairs, or as solitary individuals. A related species to the koodoo has been described under the name of Antilope Doria. The pigmy antelopes present examples of singular mem bers of the family, in that they are of exceedingly diminutive size. The Guevei (Antilope [or Cephalolophus\ pygmaea) presents two well-marked varieties, and one female speci men of the smaller variety scarcely exceeded the dimensions of a large rat. The gueveis occur on the Guinea Coast, but are also occasionally found at the Cape of Good Hope. The bush antelope (Cephalolopkiis sylvicultrix), inhabiting the districts around Sierra Leone, is also of a smaller size than the more typical antelopes, and is nearly related to the preceding forms. The harnessed antelope (Antilope scripta) (Plate II. fig. 1), so named from the white stripes with which its body is encircled, has been described as occurring in Senegal. The eland or impophoo (Boselaplius Oreas) is one of the largest of the antelopes, and is ox-like in its general pro portions and appearance. The horns are straight and erect, and the breast possesses a " dew-lap " or tuft. It inhabits the flat lands of Southern Africa. Allied to the elands, but of smaller size, we find the addax (Oryx naso- maculata). Of this species there are several varieties ; but the typical form is found in Northern Africa, and is distinguished by the elongated spiral horns. The gnus of South Africa form connecting links be tween the antelope and ox families, presenting characters in external aspect which separate them out as singular and somewhat abnormal forms. The gnu proper or wildebeest (Catoblepas Gnu) (Plate II. fig. 5), and the bastard wildebeest (Catoblepas Gorgon), are the two forms included in this genus. The head is bovine in its appear ance, and to the ox-like head are added the mane of the horse, the limbs of the stag, and the horns of the buffalo. The horns are possessed by both sexes, and are curved from their broad bases, at first downwards and for wards, their terminal portions being directed upwards and backwards. These animals resemble a small horse in size, and occur in large herds on the flat steppes of Southern Africa, although they appear to be migratory in habits, and to have a wide range in distribution over the southern half of the continent. Having thus indicated the more familiar of the ante lopes inhabiting the great African or central tract of distri bution of the family, we may next glance at the species found in the other continents. The Chinese antelope (Antilope auttnrosa), or dzerin of the Mongolian Tartars,