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SAVAGE SUDAN 



But before relating that incident, it will be appropriate 

 briefly to summarise the racial distinctions of the water- 

 buck throughout Africa. Its range extends over the 

 whole continent, from the confines of Cape Colony to 

 Sahara ; but in all that wide extension it exhibits but two 

 types worthy of separate specific rank. These two are : 



(i) IN THE SOUTH Cobus ellypsiprymmis. Known 

 as the "Common waterbuck" until East Africa was 



Two WATERBUCK BULLS. 

 (Sketched 16 miles north of Renk, March I4th, 1919.) 



discovered ! Distinguished by the conspicuous elliptic 

 band of pure white encircling an otherwise dark stern -as 

 it were, like a target. 



(2) IN THE NORTH Cobus defassa, or Sing-sing water- 

 buck, in which the white circle is replaced by an entirely 

 pale-coloured stern, similar to that in red deer and in 

 many of the antelopes see sketch above. 



No. i extends northward but in gradually deteriorat- 

 ing form till it finally peters out by the Equator ; but 

 precisely at that geographic symbol the vacated place is 

 reoccupied by a new and vigorous form, bigger, and of 



