WHITE-EARED KOB 207 



the cheek and another on the forehead. Gradually these black areas 

 increase in size, while at the same time white begins to make its 

 appearance on various parts of the face. Eventually the whole head 

 becomes black and white, the white occupying the entire surface of the 

 ears and a large portion of the forehead and cheeks. 



The assumption of a sable livery by the adult males (and in some 

 cases by both sexes) of several species of hollow-horned ruminants is 

 well known, and is evidently a specialised feature. It does not, 

 however, appear to be recognised that white may also be largely 

 developed at the same time. In many instances, as in the case of 

 the rump-patch of the bantin and the " stockings " of the gaur, the 

 white is met with in the young of both sexes. The young bantin has, 

 however, the outer side of the lower part of the legs chestnut, and it 

 is not till the animal becomes adolescent that these turn white. 

 Similarly the white rings round the eyes of adult male blackbuck 

 are not developed till the assumption of the sable livery. The large 

 white areas on the head of the white-eared kob seem, however, to be 

 unparalleled as a secondary development, and are, therefore, of more 

 than ordinary interest. 



Modern researches have shown that the senile whitening of the 

 human hair, and probably also the winter whitening of many Arctic 

 animals, is due to the work of phagocytes. In the case of the 

 present species it would seem, however, that the white hairs of the 

 adult are a new development ; and if so, we have the curious 

 phenomenon of the cessation of development of pigment in areas 

 where it was abundant in the young state of the animal. Such a 

 cessation of the production of pigment is evidently a much more 

 remarkable feature than the change of colour from chestnut to black, 

 which is what ordinarily takes place. 



White-eared kob are essentially water-loving antelopes, associating 

 in large herds, which may sometimes include two or three hundred 

 individuals. Like lechwi, these antelopes, when first starting to run, 

 or even in the middle of a gallop, frequently leap high in the air 

 several times in succession. 



VAUGHAN'S KOB 

 ( Cobus vaughani] 



For some considerable time previous to 1 906 rumours were preva- 

 lent among sportsmen as to the existence in the southern districts of 



