278 SEXUAL SELECTION: MAMMALS. [Part II. 



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- 

 cephalus hamadryas differs from th*e female not only by 

 his immense mane, but slightly in the color of the hair 

 and of the naked callosities. In the drill ( Cynocephalus 

 leucopliozus) the females and young are much paler- 

 colored, with less green, than the adult males. No 

 other member of the whole class of mammals is colored 

 in so extraordinary a manner as the adult male mandrill 

 (Cynocephalus 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." 3I When the animal 

 is excited all the naked parts become much more vividly 

 tinted. Several authors have used the strongest expres- 

 sions in describing these resplendent colors, which they 

 compare with those of the most brilliant birds. Another 

 most remarkable peculiarity is that when the great ca- 

 nine teeth are fully developed, immense protuberances of 

 bone are formed on each cheek, which are deeply fur 

 rowed longitudinally, and the naked skin over them is 

 brilliantly colored, as just described. (Fig. 67.) In the 

 adult females and in the young of both sexes these protu- 

 berances are scarcely perceptible ; and the naked parts 

 are much less brightly colored, the face being almost 



31 Gervais, 'Hist. Nat. des Mammiferes,' 1854, p. 103. Figures are 

 given of the skull of the male. Desmarest, ' Mammalogie,' p. 10. 

 Geoffroy St.-Hilaire and F. Cuvier, 'Hist. Nat. des Mainm.' 1824, torn, i. 



