92 ANIMAL LIFE IN AFRICA 



when dashing at full speed through the bush in single 

 file, the task of following the leader might be rendered 

 more easy. The opponents of the theory, on the other 

 hand, point out that smell and not sight is the sense 

 made use of in such matters, and that in any case 

 colours would be ineffective at night. 



The average height of the males at the withers is 

 some thirty-four inches, and their beautiful lyre-shaped 

 horns reach, in South Africa, a length of about two 

 feet round the curve, while in East Africa they often 

 exceed this by six or seven inches. In Northern 

 Rhodesia and Nyasaland, on the other hand, the heads 

 are generally smaller than in the south. It is remarkable 

 how this variety in size tends to occur locally amongst 

 certain species of the game ; were it due to the influence 

 of climate, it might be expected to affect all types in even 

 degree ; but some East African species are seen to carry 

 heads of lesser, and certain Rhodesian forms of greater 

 dimensions than their South African prototypes. Local 

 influence no doubt counts for something, for the impalas 

 found on the stony slope of the Lebombo Hills, in the 

 Transvaal Game Reserve, attain, in common with pther 

 species there, to a greater length of horn, and a heavier 

 bodily weight than their brethren habitually resident 

 in the flat bush country. Impala females are hornless, 

 and exceed the males in number. 



There is no prettier sight than a troop of impala feeding 

 in some open glade of their favourite bush, when they 

 fancy themselves unobserved. The rams dotted here 

 and there amongst the preponderating numbers of the 

 other sex, pick their way daintily along, their heads 

 erect, their chests puffed out, and their whole bearing 

 stamped with the sense of conscious superiority. The 

 females, ever wary and alert for danger, glance constantly 



