MAMMALS. 623 



stems of the bamboo as to assist greatly in concealing him 

 from his approaching prey." But this view does not 

 appear to me satisfactory. We have some slight evidence 

 that his beauty may be due to sexual selection, for in two 

 species of Felis the analagous marks and colors are rather 

 brighter in the male than in the female. The zebra is con- 

 spicuously striped, and stripes cannot afford any protection 

 on the open plains of S. Africa. Burchell* in describing 

 a herd says: ** Their sleek ribs glistened in the sun, and the 

 brightness and regularity of their striped coats presented a 

 picture of extraordinary beauty, in which probably they are 

 not surpassed ty any other quadruped." But as through- 

 out the whole group of the Equida3 the sexes are identical 

 in color we have here no evidence of sexual selection. 

 Nevertheless he who attributes the white and dark vertical 

 stripes on the flanks of various antelopes to this process, 

 will probably extend the same view to the royal tiger and 

 beautiful zebra. 



AVe have seen in a former chapter that when young ani- 

 mals belonging to any class follow nearly the same habits 

 of life as their parents, and yet are colored in a different 

 manner, it may be inferred that they have retained the 

 coloring of some ancient and extinct progenitor. In the 

 family of pigs, and in the tapirs, the young are marked 

 with longitudinal stripes, and thus differ from all the exist- 

 ing adult species in these two groups. With many kinds of 

 deer the young are marked with elegant white spots, 

 of which their parents exhibit not a trace. A graduated 

 series can be followed from the axis deer, both sexes of 

 which at all ages and during all seasons are beautifully 

 spotted (the male being rather more strongly colored than 

 the female), to species in which neither the eld nor the 

 young are spotted. I will specify some of the steps in this 

 series. The Mantchurian deer (Cei'vus niantchuriiws) is 

 spotted during the whole year, but, as I have seen in the 

 Zoological Gardens, the spots are much plainer during the 

 summer, when the general 'color of the coat is lighter than 

 during the winter, when the general color is darker and the 

 horns are fully developed. In the hog-deer (Hyelaplnis 

 porcimis) the spots are extremely conspicuous during the 

 summer when the coat is reddish-brown, but quite aisap- 



* Travels iii South Africa," 1824, vol. ii, p. 315. 



