296 SEXUAL SELECTION : MAMMALS. [Pakt IL 



both sexes when adult liave their faces colored in llie 

 same nianniT. 



Althougli, according to our taste, nuiuy kinds of mon- 

 keys are far from beautiful, other species are universally 

 admired for their elegant ai)i)i'arance and briglit colors. 

 The /Sijnuojnthectis nemmus, tliough peculiarly colored, is 

 described as extremely pretty ; the orange-tinted face is 

 surrounded by long whiskers of glossy whiteness, with a 

 line of chestnut red over the eyebrows ; the fur on the 

 back is of a delicate gray, with a square patch on the 

 loins, the tail and the forearms all of a pure white ; a 

 gorget of chestnut surmounts the chest ; the hind-thighs 

 are black, with the legs chestmit red. I will mention only 

 two other monkeys on account of their beauty ; and I 

 have selected these as they present slight sexual differ- 

 ences in color, which renders it in some degree probable 

 that both sexes owe their elegant a2)pearance to sexual 

 selection. In the mustache-monkey •( 6'tTco/)^7/tcc^<5 ce- 

 2)}n(s), the general color of the fur is mottled greenish, 

 with tlie throat white ; in the male the end of the tail is 

 chestnut ; but the face is the most ornamented part, the 

 skin being chiefly bluish-gray, shading into a blackish 

 tint beneath the eyes, with the upper lip of a delicate 

 blue, clothed on the lower edge with a thin black mus- 

 tache; the whiskers are orange-colored, with the upper 

 ])art black, forming a band which extends backward to 

 the ears, the latter being clothed with whitish hairs. In 

 the Zoological Society's Gardens I have often overheard 

 visitors admiring the beauty of another monkey, deserv- 

 edly called Cercopithecus Diana (Fig. 76) ; the general 

 color of the fur is gray ; 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 chestnut ; in the 

 male the inner sides of the thighs and the abdomen are 

 delicate fawn-colored, and the top of the head is black ; 



