40 AFRICAN NATURE NOTES CHAP. 



the white rump patch so conspicuous in the bonte- 

 bok has become pale brown, as, I think, through 

 the influence of the dull monotonous colours of the 

 dreary, dull -coloured country in which it lives. 

 Ages ago no doubt the bontebok spread north- 

 wards through the karroo into the countries beyond 

 the Orange and the Vaal rivers, but the gradual 

 desiccation of the whole of South-Western Africa, 

 which has been going on for a very long time, must 

 have gradually driven all the bonteboks outside the 

 Cape peninsula northwards to the Orange river, 

 and completely separated them from their relatives 

 still living near Cape Agulhas. These latter have 

 retained all their richness of coloration brought 

 about by the influence of their very striking sur- 

 roundings, the deep blue of the sea, the snow on 

 the mountains, and the bloom of innumerable wild 

 flowers. The northern herds moved into open 

 plains, in themselves very similar to the plains near 

 Cape Agulhas, but they are never carpeted with 

 wild flowers, nor are they skirted by a deep blue 

 sea, nor ever overlooked by snow-covered mountains. 

 Is it not possible that the differences which exist 

 to-day between the coloration of the bontebok and 

 the blesbok are entirely the result of the absence 

 of any kind of colour but various monotonous shades 

 of brown in the countries in which the latter species 

 has now been living for a long period of time ? 



Not only has the rich and beautifully variegated 

 body colouring of the bontebok become an almost 

 uniform dark brown in the blesbok, but the snow- 

 white disc on the rump of the former animal has 

 turned to a pale brown in the latter, whilst the 

 area of white on the face and legs of the bontebok 

 has already been considerably contracted in the 

 blesbok. 



Personally, I look upon the blesbok as a faded 

 bontebok ; faded because it moved northwards out 



