Chap. XVII. Mammals — Law of Battle. 503 



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 of so many animals. With female desz 

 the development during each recurrent season of great branching 

 horns, and with female elephants the development of immense 

 tusks, would be a great waste of vital power, supposing that 

 they were of no use to the females. Consequently, they would 

 have tended to be eliminated in the female through natural 

 selection; that is, if the successive variations were limited in 

 their transmission to the female sex, for otherwise the weapons 

 of the males would have been injuriously affected, and this 

 would have been a greater evil. On the whole, and from the 

 consideration of the following facts, it seems probable that when 

 the various weapons differ in the two sexes, this has generally 

 depended on the kind of transmission which has prevailed. 



As the reindeer is the one species in the whole family of Deer, 

 in which the female is furnished with horns, though they are 

 somewhat smaller, thinner, and less branched than in the male, 

 it might naturally be thought that, at least in this case, they 

 must be of some special service to her. The female retains her 

 horns from the time when they are fully developed, namely, in 

 September, throughout the winter until April or May, when she 

 brings forth her young. Mr. Crotch made particular enquiries 

 for me in Norway, and it appears that the females at this season 

 conceal themselves for about a fortnight in order to bring forth 

 their young, and then reappear, generally hornless. In Nova 

 Scotia, however, as I hear from Mr. H. Eeeks, the female some- 

 times retains her horns longer. The male on the other hand 

 casts his horns much earlier, towards the end of November. As 

 both sexes have the same requirements and follow the same 

 habits of life, and as the male is destitute of horns during the 

 winter, it is improbable that they can be of any special service 

 to the female during this season, which includes the larger part 

 of the time during which she is horned. Nor is it probable 

 that she can have inherited horns from some ancient pro- 

 genitor of the family of deer, for, from the fact of the females of 

 so many species in all quarters of the globe not having horns, 

 we may conclude that this was the primordial character of the 

 group. 8 



The horns of the reindeer are developed at a most unusually 



8 On the structure and shedding regard to the American variety or 



J>f the horns of the reindeer, Hoii'- species ; also Major W. Ross King, 



berg, ' Amoenitates Acad.' vol. iv. ' The Sportsman in Canada,' 1 86'i } 



1788, p. 149. See Richardson, > . 80. 

 Fauna Bor. American;!.' p. 241, in 



