544 



THE DESCENT OP MAN. 



cles tho sexes resemble each other in color, but in some, as we 

 have seen, the males differ from the females, especially in the 

 color of the naked parts of the skin, in the development of the 

 heard, whiskers, and mane. Many species are colored either in 

 so extraordinary or so beautiful a manner, and are furnished 

 with such curious and elegant crests of hair, that we can hardly 

 avoid looking at these characters as having been gained for the 



I fi'*'? 



Fig. 73. Head of Semnopithecus Fig. 74. Head of Cebus capucinus. 

 comatus. 



Fig. 75. Head of Ateles marginatus. 



Fig. 76. Head of Cebus 

 vellerosus. 



sake of ornament. The accompanying figures (figs. 72 to 76) 

 serve to show the arrangement of the hair on the face and head 

 in several species. It is scarcely conceivable that these crests of 

 hair, and the strongly contrasted colors of the fur and skin, can 

 be the result of mere variability without the aid of selection; 

 and it Is inconceivable that they can be of use in any ordinary 

 way to these animals. If so, they have probably been gained 

 through sexual selection, though transmitted equally, or almosV 



