2 36 THE OX AND ITS KINDRED 
distinct species, as indeed was the view taken by the 
older naturalists. But it happens that in various 
parts of western and central Africa there occur a 
number of different types of buffaloes which collec- 
tively serve to form an almost complete gradation 
from the large black to the small red animal ; and it 
accordingly seems the most logical course to regard 
all these local variations as representing races or 
phases of a single exceedingly variable species. 
Support to this view is afforded by the circum- 
stances that analogous variations occur in other 
groups of African big game animals. Giraffes, for 
instance, are characterised by the pure white lower 
portions of the legs and the strong development of 
the unpaired frontal horns in the north of Africa, 
whereas in the south they have fawn-coloured and 
spotted legs and a rudimentary frontal horn, while 
in the intervening districts intermediate conditions 
obtain in these respects. Consequently, all these 
phases are regarded as referable to a single species. 
Again, the difference between the black-and-white 
striped Grant's bontequagga, or zebra, of north- 
eastern Africa, with its legs striped down to the 
hoofs, and Burchell's bontequagga, or zebra, of 
southern Africa, in which the legs are white and 
unstriped, while the body - markings consist of 
chocolate stripes on an orange-tawny ground with 
fainter intermediate "shadow" stripes, is enormous; 
and yet these two extremes are so inseparably 
connected that they cannot be regarded otherwise 
than as local races of one and the same species. 
Much the same state of things obtains in the case of 
the local forms of bushbuck. 
In a continent of the size of Africa — a size not 
