234 SEXUAL SELECTION: MAMMALS. [Part II. 



species of deer, either normally or occasionally, exhibit 

 rudiments of horns ; thus the female of Cervulus moscTia- 

 (us has " bristly tufts, ending in a knob, instead of a horn ; " 

 and " in most specimens of the female Wapiti ( Cervus 

 Canadensis) there is a sharp bony protuberance in the 

 place of the horn." 10 From these several considerations 

 we may conclude that the possession of fairly well- 

 developed horns by the female reindeer, is due to the 

 males having first acquired them as weapons for fighting 

 with other males ; and, secondarily, to their development 

 from some unknown cause at an unusually early age in 

 the males, and their consequent transmission to both 

 sexes. 



Turning to the sheath-horned ruminants: with ante- 

 lopes a graduated series can be formed, beginning with 

 the species, the females of which are completely destitute 

 of horns — passing to those which have horns so small as 

 to be almost rudimentary, as in Antilocapra Americana 

 — to those which have fairly well-developed horns, but 

 manifestly smaller and thinner than in the male, and 

 sometimes of a different shape, 11 and ending with those in 

 which both sexes have horns of equal size. As with the 

 reindeer, so with antelopes, there exists a relation be- 

 tween the period of the development of the horns* and 

 their transmission to one or both sexes ; it is therefore 

 probable that their presence or absence in the females of 



female chamois ('Chamois Hunting in the Mountains of Bavaria,' 1860, 

 2d edit. p. 363), says, " not only was the head very male-looking, but along 

 the back there was a ridge of long hair, usually to be found only in 

 bucks." 



10 On the Cervulus, Dr. Gray, ' Catalogue of the Mammalia in British 

 Museum,' part iii. p. 220. On the Cervus Canadensis or Wapiti see Hon. 

 J. D. Caton, 'Ottawa Acad, of Nat. Sciences,' May, 1868, p. 9. 



11 For instance, the horns of the female Ant. Euclwre resemble those 

 of a distinct species, viz. the Ant. Dorcas var. Corine^ see Desmarest, 

 1 Mammalogie,' p. 455. 



