ZEBRAS AND QUAGGAS 207 



the colour-pattern of the animals under considera- 

 tion. In the zebra, Gravy's zebra, and the more 

 northern races of the bontequagga the legs are 

 striped right down to the hoofs, while in the last- 

 mentioned animals the stripes extend downwards 

 to meet the longitudinal belly-stripes. Now all 

 these animals inhabit more or less broken or bush- 

 covered country. On the other hand, the quagga 

 and the typical southern race of the bontequagga 

 inhabited the open South African plains, and in 

 these the legs are lighter coloured than the body, 

 while in some forms of the quagga and in the 

 southern bontequaggas the whole of the under-parts 

 and much of the buttocks are likewise white. 

 Moreover, in the latter the black stripes of the 

 northern bontequaggas are toned down to brown 

 and faint orange shadow-stripes intercalated. 

 Here, in fact, a totally different kind of colour-pro- 

 tection comes into play ; namely, one common to a 

 large number of herbivorous animals living on open 

 plains, and already referred to in connection with 

 the kiang and onager. In this type of colouring 

 the under surface of the body and the limbs are 

 conspicuously lighter (often white) than the upper 

 parts, so that when the animal is standing in bright 

 sunlieht the liofht colouring of the lower surface 

 completely counteracts the effect of the dark shade 

 cast by the body, and thus produces more or less 

 complete invisibility. Much the same effect is 



