go THE MAMMALS OF ETHIOPIAN AFRICA 



are so called from their well-known habit of leaping into the air with their backs 



arched and the fan displayed. At one time they existed in countless numbers on 



the dry open country, across which they migrated in tens of thousands to the limit 



of their western range at the breeding-season in order that the fawns might find 



suitable food in the fresh pastures. For an account of these " trekbokken," as these 



migrations are called by the Boers, the reader may refer to Gordon Cumming's 



well-known volume. 



Central Somaliland is the home of the dibatag (Ammodorcas 

 Dibatag. _ a \ 



clarkei), a species closely related to the true gazelles, but differing by 



the long, neck, long thin tail, and the shape of the black horns, which curve 



upwards and forwards, somewhat like those of a reedbuck. When running, 



these antelopes bend their long necks backwards so that the horns of the 



bucks nearly touch the tail, which is curved upwards and forwards. The 



females are hornless. 



Another remarkable species from north-eastern Africa is the 

 Gerenuk. ... 



gerenuk (Ldhocramus walleri), which ranges from Somaliland to 



German East Africa. This is a gazelle-like antelope, in which the length of the 



neck has caused it to be likened to a miniature giraffe. The horns resemble in 



shape a long reversed S, curving forwards, upwards, backwards, and then forwards 



again so as to form a sort of hook. The females resemble those of the dibatag 



in lacking horns. Both sexes have a large glandular inflated area round the eye. 



The general colour of the upper-parts is rufous cinnamon, with a broad band of 



darker rufous along the middle line of the back. Gerenuk are generally met 



witli on rocky ground sparsely covered with thorn-bushes, and never on treeless 



plains. The leaves of trees and bushes, rather than grass, form their chief food, 



and when browsing on trees they may be seen standing on their hind-legs with 



their fore-feet reared against the stern, and the giraffe-like neck stretched to its 



fullest extent. They were known to the ancient Egyptians, as is attested by a 



sketch of a male and female incised on a slab of slate. 



To mention even by name the whole of the numerous species 



G3.Z6II6S 



of true gazelles to be found in Ethiopian Africa would be out of 

 place in this work, and brief reference to some of the more striking species must 

 accordingly suffice. The largest members of the genus are the three so-called giant 

 gazelles, which have been suggested to be modified northern representatives of the 

 springbuck. One of the most interesting of these is the dama (Gazella da/ma), two 

 of the local races of which are known respectively as the addra and the mhor. This 

 gazelle is the largest of the whole group, standing from 36 to 37 inches at the 

 shoulder. In colour it presents a remarkable analogy to the white oryx, the 

 greater portion of the body being white with patches of chestnut, which may 

 include most of the neck. This pale colouring is an adaptation to a desert exist- 

 ence; the dama ranging over the desert tracts of central North Africa from 

 Senegambia to Kordofan and Sennar, so that it forms a kind of connecting link 

 between the faunas of North and Ethiopian Africa. The black lyrate horns are of 

 medium length. Of a more normal type of colouring is the handsome Sommerring's 

 gazelle (G. scemmerringi), ranging from the Abyssinian coast of the Red Sea, 

 through Berbera, the east side of Sennar, Danakil, and Bora-Gallalaud to Somaliland, 



