SEXUAL SELECTION 



687 



species of Macacus," and, as we have seen, with the manes 

 of some species of baboons. But with most kinds of mon- 

 keys the various tufts of hair about the face and head are 

 alike in both sexes. 



The males of various members of the ox family (Bovi- 

 dse) and of certain antelopes are furnished with a dewlap, 



v^-- 



Fio. 68.— Pitheoia satanas, male (from Brehm). 



or great fold of skin on- the neck, which is much less devel- 

 oped in the female. 



Now, what must we conclude with respect to such sexual 

 differences as these ? N"o one will pretend that the beards 

 of certain male goats, or the dewlap of the bull, or the crests 

 of hair along the backs of certain male antelopes, are of any 

 use to them in their ordinary habits. It is possible that the 

 immense beard of the male Pithecia, and the large beard of 



" Rengger, "Saugethiere, " etc., s. 14; Desmarest, "Mammalogie, " p. 66. 



