312 SEXUAL selection: mammals. PartIL 



are orange-coloured, with tlie upper partblack, forming 

 a band which extends backwards to the ears, the latter 

 being clothed with wdiitish hairs. In the Zoological 

 Society's Gardens I have often overheard visitors ad- 

 miring the beauty of anotlier monkey, deservedly called 

 Cercopithecus Diana (fig. 76) ; the general colour of the 

 fur is grey ; the chest and inner surface of the fore-legs 

 are white ; a large triangular defined, space on the hinder 

 part of the back is rich chesnut ; in the male the inner 

 sides of tJie thighs and the abdomen are delicate fawn- 

 coloured, and the top of the head is black ; the face and 

 ears are intensely black, finely contrasted with a wdiite 

 transverse crest over the eye-browns and with a long 

 white peaked beard, of which the basal portion is 

 black.^^ 



In these and many other monkeys, the beauty and 

 singular arrangement of their colours, and still more the 

 diversified and elegant arrangement of the crests and 

 tufts of hair on their heads, force the conviction on my 

 mind that these characters have been acquired through 

 sexual selection exclusively as ornaments. 



Summary. — The law of battle for the possession of the 

 female appears to prevail throughout the whole great 

 class of mammals. Most naturalists will admit that 

 the greater size, strength, courage, and pugnacity of the 

 male, his special weapons of offence, as well as his 

 special means of defence, have all been acquired or 

 modified throuirh tliat form of selection which I have 



*^ I Lave seen most of the above-named monkeys in the Zoological 

 Society's Gardens. Tiie description of the SemnopHliecus nemxus is 

 taken from Mr. W. C. Martin's ' Nat. Hist, of Mammalia,' 1841, p. 4G0; 

 see also p. 475, 528. 



