DESERTS AND THEIR INHABITANTS 131 
coloured members of the group; and lions are likewise 
to a great extent inhabitants of deserts—as, indeed, is 
true of tawny and pale-coloured animals in general. 
All the animals above mentioned belong, however, to 
widely spread groups, which are common to the desert 
tracts of both Africa and Asia, and they do not, therefore, 
serve to prove the antiquity of any particular desert, as 
they or their ancestors might have (and probably did) 
migrate from one desert to another. Birds of such groups 
are, of course, even more untrustworthy than mammals, 
owing to their power of flight. And among those referred 
to, some, such as the sand-grouse, can scarcely claim to 
be regarded as exclusively desert birds, since they are 
partial to any open sandy plains, like those of the Punjab, 
or even Norfolk. 
The case is, however, very different with certain of the 
larger mammals, a notable instance being afforded by the 
antelopes allied to the South African gemsbok (Oryx). 
All the members of this group are inhabitants of more or 
less sandy open districts, and never range eastwards of 
Arabia, or possibly Bushire. The gemsbok itself, together 
with the beisa of Eastern and North-eastern Africa, are 
inhabitants of districts which do not, for the most part, 
come under the designation of typical deserts. And we 
accordingly find that both are by no means very pale- 
coloured animals, while both are remarkable for the bold 
bands of sable ornamenting their face and limbs. On the 
borders of the Sahara there occurs, however, a very 
different member of the group—the sabre-horned oryx 
(O, leucoryx)—differing from the others by its curving horns, 
and likewise by the extreme pallor of its coloration, which 
is mostly dirty white, with pale chestnut on the neck and 
under-parts. Obviously this species has been specially 
