Chap. XYII. LAW OF BATTLE. 243 



It is not probable, at least in most cases, that the females 

 have actually been saved from acquiring such weapons, 

 owing- to their being useless and superfluous, or in some 

 way injurious. On the contrary, as they are often used 

 by the males of many animals for various purposes, 

 more especially as a defence against their enemies, it is 

 a surprising fact that they are so poorly developed or 

 quite absent in the females. No doubt with female deer 

 the development during each recurrent season of great 

 branching horns, and with female elephants the deve- 

 lopment of immense tusks, would have been a great 

 waste of vital power, on the admission that they were 

 of no use to the females. Consequently variations in 

 the size of these organs, leading to their suppression, 

 would have come under the control of natural selection, 

 and if limited in their transmission to the female off- 

 spring would not have interfered with their develop- 

 ment through sexual selection in the males. But how 

 on this view can we explain the presence of horns in the 

 females of certain antelopes, and of tusks in the females 

 of many animals, which are only of slightly less size 

 than in the males ? The explanation in almost all cases 

 must, I believe, be sought in the laws of transmission. 



As the reindeer is the single species in the whole 

 family of Deer in w^iich the female is furnished with 

 horns, though somewhat smaller, thinner, and less 

 branched than in the male, it might naturally be 

 thought that they must be of some special use to her. 

 There is, however, some evidence x>pposed to this view. 

 The female retains her horns from the time when they 

 are fully developed, namely in September, throughout 

 the winter, until May, when she brings forth her young ; 

 whilst the male casts his horns much earlier, towards the 

 end of November. As both sexes have the same require- 

 ments and follow the same habits of life, and as the male 



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