SEXUAL SELECTION 65l 



The horns of the reindeer are developed at a most un- 

 usually early age; but what the cause of this may be is 

 not known. The effect has apparently been the transfer- 

 ence of the horns to both sexes. We should bear in mind 

 that horns are always transmitted through the female, and 

 that she has a latent capacity for their development, as we 

 see in old or diseased females." Moreover, the females of 

 some other species of deer exhibit, either normally or occa- 

 sionally, rudiments of horns; thus the female of Cervulus 

 moschatus 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." "" 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 con- 

 sequent transference to both sexes. 



Turning to the sheath-horned ruminants: with antelopes 

 a graduated series can be formed, beginning with species 

 the females of which are completely destitute of horns — 

 passing on to those which have horns so small as to be 

 almost rudimentary (as with the Antilocapra americana, in 

 which species they are present in only one out of four 

 or five females") — to those which have fairly developed 

 horns, but manifestly smaller and thinner than in the male 

 and sometimes of a different shape" — and ending with those 



» Isidore G«ofiroy St.-Hilaire, "Esaais de Zoolog. G&^rale," 1841, p. 513. 

 Other masculine characters, besides the horns, are sometimes similarly trans- 

 ferred to the female ; thus Mr. Boner, in speaking of an old 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." 



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

 Museum," part. iii. p. 220. On the Gervus canadensis or wapiti, see Hon. 

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



" lam indebted to Dr. Canfield for this information; see, also, his paper 

 in "Proc. Zoolog. Soc," 1866, p. 105. 



'* For instance the horns of the female Antilocapra euchore resemble those 



