90 SKXUAL DIMORPHISM 



of deer in Canada, states that this question was of the 

 greatest scientific importance, and that he took pains to 

 investigate it to his satisfaction, with the result that he was 

 entirely convinced that there was no truth in the belief 

 above mentioned. The spike-horn bvxks seen and hilled in the 

 Adirondaclcs were all yearling bucks with their first antlers. 

 In all species of Cervus the horns which first grow are simple, 

 pointed, unbranched spikes, and to prove the existence of 

 spike-horned bucks as a variety, it would be necessary to 

 show that when they cast their horns they developed simple 

 spikes every year throughout life. No attempt was made to 

 produce evidence of this, and Caton describes cases which 

 came under his own observation in which spike-horned bucks 

 of large size, which might have been supposed to be full 

 grown, developed branched horns in the following year. The 

 spike-horns belonging to stags supposed to be adult were 

 stated to be longer than the normal simple horns of yearling 

 stags, but Caton points out that in the first place accurate 

 measurements were not made, and in the second, that the 

 length of normal simple antlers varies considerably in different 

 individuals. 



In the family Cervidse the Reindeer Rangifer forms a 

 single exception in the fact that both sexes bear antlers, 

 although those of the female are considerably smaller and 

 less branched than those of the male. Darwin lays much 

 stress on the fact that in the Keindeer the horns in both 

 males and females first appear at a period of life considerably 

 earlier than in the males of the other species in the family. 

 In seven species in which the males alone bear antlers, he 

 ascertained from trustworthy observers that they first appear 

 at periods varying from nine months after birth in the 

 roebuck, to ten, twelve, or even more months in other and 

 larger species ; while in the Reindeer, according to Professor 

 Nilsson, they appear in both sexes within four or five weeks 



