294 SEXUAL SELECTION : MAMMALS. Paht II. 



the adult male and with the young of both sexes, as I 

 saw in the Gardens, neither the naked skin at the 

 posterior end of the body, nor the face, shew a trace 

 of red. It appears, however, from some published 

 accounts, that the male does occasionally, or during 

 certain seasons, exhibit some traces of the red. Although 

 he is thus less ornamented than the female, vet in the 

 larger size of bis body, larger canine teeth, more de- 

 veloped whiskers, more prominent superciliary ridges, 

 he follows the common rule of the male excellins^ the 

 female. 



I have now given all the cases known to me of a dif- 

 ference in colour between the sexes of mammals. The 

 colours of the female either do not differ in a sufficient 

 degree from those of the male, or are not of a suitable 

 nature, to afford her protection, and therefore cannot be 

 explained on this principle. In some, perhaps in many 

 cases, the differences may be the result of variations 

 confined to one sex and transmitted to the same sex, 

 without any good having been thus gained, and there- 

 fore without the aid of selection. We have instances 

 of this kind with our domesticated animals, as in the 

 males of certain cats being rusty -red, whilst the females 

 are tortoise-shell coloured. Analogous cases occur 

 under nature ; Mr. Bartlett has seen manv black var- 

 ieties of the jaguar, leopard, vulpine phalanger and 

 wombat ; and he is certain that all, or nearly all, were 

 males. On the other hand, both sexes of wolves, 

 foxes, and apparently of American squirrels, are occa- 

 sionally born black. Hence it is quite possible that 

 with some mammals the blackness of the males, especi- 

 ally when this colour is congenital, may simply be the 

 result, without the aid of selection, of one or more 

 variations having occurred, which from the first were 



