614 THE DESCENT OF MAN, 



Cercopitliecns diana, the head of the adult male is of an 

 intense black, while that of the female is dark gray; in the 

 former the far between the thighs is of an elegant fawn- 

 color, in the latter it is paler. In the beautiful and curious 

 mustache monkey (Cercopithecus cephus) the only diiTer- 

 ence between the sexes is that the tail of the male is 

 chestnut and that of the female gray; but Mr. Bartlett 

 informs me that all the hues become more pronounced in 

 the male when adult, while in the female they remain as 

 they were during youth. According to the colored figures 

 given by Solomon Miiller, the male of Semnnpitliecus 

 chrysomelas is nearly black, the female being pale brown. 

 In the Cercopithecus cynosurus and yriseoviridis one part 

 of the body, which is confined to the male sex, is of the 

 most brilliant blue or green, and contrasts strikingly with 

 the naked skin on the hinder part of the body, which is 

 vivid red. 



Lastly, in the baboon family, the adult male of Cyno- 

 cephalns hanw.dryas differs from the female not only by his 

 immense mane, but slightly in the cole;* of the hair'and 

 of the nalied callosities. In the drill (C. leiicophceus) the 

 females aud young are much paler colored, with less green 

 than the adult males. No other member in the whole 

 class of mammals is colored in so extraordinary a manner 

 as the adult male mandrill (C. mormon). The face at this 

 age becomes of a fine blue, with the ridge and tip of the 

 nose of the most brilliant red. According to some authors 

 the face is also marked with whitish stripes, and is shaded 

 in parts with black, but the colors appear to be variable. 

 On the forehead there is a crest of hair, and on the chin a 

 yellow beard. " Toutes les parties superieures de leurs 

 cuisses et le grand espace nu de leurs fesses sont egalement 

 colores du rouge le plus vif, avec un melange de bleu qui 

 ne manque reellement pas d'elegance."* "When the animal 

 is excited ali the naked parts become much more vividly 

 tinted. Several authors have used the strongest expres- 

 sions in describing these resplendent colors, which they com- 

 pare with those of the most brilliant birds. Another remark- 



*Gervais, -'Hist. Nat. des Mamm: feres," 1854, p. 103. Figures 

 are given of the skull of the male. Also Desmarest, " Mammal- 

 ogie," p. 70. Oeoffroy St.-Hilaire and F. Cuvier, "Hist. Nat. des 

 Mamin.," 1824, torn. i. 



