ORIGIN AND USES OF COLOUR IN ANIMALS 



219 



of Africa — we find many distinctiye marlvings of a similar 

 kind. The gazelles have variously striped and banded faces, 

 besides white patches behind and on the flanks, as shown 

 in the woodcut. The spring-bok has a white patch on the 

 face and one on the sides, ^viih a curiously distinctive white 

 stripe above the tail, which is nearly concealed when the 

 animal is at rest by a fold of skin but comes into full view 

 when it is in motion, being thus C[uite analogous to the 



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^^m% 



Fig. 18.— Gazella scemraerringi. 



upturned white tail of the rabbit. In the pallah the 

 white rump -mark is bordered with black, and the peculiar 

 shape of the horns distinguishes it when seen from the 

 front. The sable-antelope, the gems-bok, the oryx, the hart- 

 beest, the bonte-bok, and the addax have each peculiar white 

 markings ; and they are besides characterised by horns so 

 remarkably different in each species and so conspicuous, that 

 it seems probable that the peculiarities in length, t^dst, and 

 curvature have been differentiated for the purpose of recogni- 

 tion, rather than for any speciality of defence in species whose 

 general habits are so similar. 



