246 SEXUAL selection: mammals. Part II. 



is tlierefore jorobable that their presence or absence in 

 the females of some species, and their more or less per- 

 fect condition in the females of other species, depend, 

 not on their being of some special use, but simply on 

 the form of inheritance which has prevailed. It ac- 

 cords with this view that even in the same restricted 

 genus both sexes of some species, and the males alone 

 of other species, are thus provided. It is a remarkable 

 fact that, although the females of Antilope hezoartica 

 are normally destitute of horns, Mr. Blyth has seen no 

 less than three females thus furnished ; and there was 

 no reason to suppose that they were old or diseased. 

 The males of this species have long straight spirated 

 horns, nearly parallel to each other, and directed back- 

 wards. Those of the female, when present, are very 

 different in shape, for they are not spirated, and 

 spreading widely bend round, so that their points are 

 directed forwards. It is a still more remarkable fact 

 that in the castrated male, as Mr. Blyth informs me, the 

 horns are of the same peculiar shape as in the female, 

 but lonoer and thicker. In all cases the differences 

 between the horns of the males and females, and of 

 castrated and entire males, probably depend on various 

 causes, — on the more or less complete transference of 

 male characters to the females, — on the former state 

 of the progenitors of the species, — and partly perhaps on 

 the horns being differently nourished, in nearly the same 

 manner as the spurs of the domestic cock, w^hen inserted 

 into the comb or other parts of the body, assume various 

 abnormal forms from being differently nourished. 



In all the wild species of goats and sheep the horns 

 are larger in the male than in the female, and are some- 

 times quite absent in the latter.^^ In several domestic 



^^ Gray, ' Catalogue Mamm. Brit. Mus." j)ait iii. 1852, p. 160. 



