THE MIGRATIONS OF MAMMALS. 257 



altogether before want has enfeebled their powers or broken their 

 stubborn wills. Travellers describe with enthusiasm the spectacle 

 presented by such a herd of wild horses on the march. Far into 

 the distance stretches the sandy plain, its shimmering red ground- 

 colour interrupted here and there by patches of sunburnt grass, its 

 scanty shade supplied by a few feathery-leaved mimosas, and, as far 

 away as the eye can reach, the horizon is bounded by the sharp lines 

 of mountains quivering in a bluish haze. In the midst of this land- 

 scape appears a cloud of dust which, disturbed by no breath of air, 

 ascends to the blue heavens like a pillar of smoke. Nearer and 

 nearer the cloud approaches, until at length the eye can distinguish 

 living creatures moving within it. Soon the brightly-coloured and 

 strangely-marked animals present themselves clearly to the specta- 

 tor's gaze; in densely thronged ranks, with heads and tails raised, 

 neck and neck with the quaintly-shaped gnus and ostriches which 

 have joined their company, they rush by on their way to a new, 

 and possibly far-distant feeding-ground, and ere the onlooker has 

 recovered himself, the wild army has passed by and is lost from 

 view in the immeasurable steppe. 



The antelopes, which are also driven out by winter, do not 

 always follow the same paths, but usually travel in the same direc- 

 tion. None is more numerous or more frequently seen than the 

 springbok, one of the most graceful and beautiful gazelles with 

 which we are acquainted. Its unusual beauty and agility strike 

 everyone who sees it in its wild state, now walking with elastic step, 

 now standing still to feed, now springing about in playful leaps, 

 and thus disclosing its greatest ornament, a mane-like snow-white 

 tuft of hair, which at a quieter pace is hidden in a longitudinal 

 groove of the back. None of the other antelopes, when forced to 

 migrate, assemble in such numerous herds as this one. Even the 

 most vivid description cannot convey to one who has not seen a herd 

 of springboks on their journey any adequate idea of the wonderful 

 spectacle. After having congregated for weeks, perhaps waiting for 

 the first shower of rain, the springboks at last resolve to migrate. 

 Hundreds of the species join other hundreds, thousands other thou- 

 sands, and the more threatening the scarcity, the more torturing 



