THE GREY OR VAAL RHEBOK 



mature males, and one old ram which assumes the 

 leadership. Solitary old outcast rams are occasion- 

 ally seen. 



They chiefly inhabit the flat tops and sides of the 

 mountain ranges and high hills. I have, however, 

 frequently observed them at dusk on the tops and 

 sides of low, grassy or rock-strewn hills, and when 

 disturbed they made off along these hills, and if 

 hard pressed they descended to the plains and 

 headed for the nearest range of mountains. 



When feeding or at rest, a sentinel keeps guard 

 on an adjacent elevation in the shape of a hillock 

 or kopje, and gives the alarm by uttering a sharp 

 snort or coughing sound, whereupon the troop, led 

 by the old ram, retreat at a rapid pace, usually in a 

 direction previously decided upon. When making 

 off they present a rather novel sight, owing to their 

 habit of jerking up the hindquarters at every bound 

 and holding the tail erect, exposing the white 

 under-surface. 



They feed during the early morning and evening, 

 chiefly on grass, and rest during the day amongst 

 patches of bush and boulders, or in the sheltered 

 gullies on the high slopes ; or on the open plateaus 

 amongst the loose stones, boulders or grass. 



They descend to the lower lands at night to drink 

 and feed upon the more succulent grasses which 

 thrive on these lower levels, and ascend to their 

 mountainous retreats before sunrise. 



They are often attacked by a species of Bot-fly 

 83 



