804 THE DESCENT OF MAN 



The wattle in the Englisli Carrier pigeon and the crop in 

 the Pouter are more highly developed in the male than 

 in the female; and, although these characters have been 

 gained through long-continued selection by man, the slight 

 differences between the sexes are wholly due to the form of 

 inheritance which has prevailed; for they have arisen, not 

 from, but rather in opposition to, the wish of the breeder. 



Most of our domestic races have been formed by the ac- 

 cumulation of many slight variations; and as some of the 

 successive steps have been transmitted to one sex alone, 

 and some to both sexes, we find in the different breeds of 

 the same species all gradations between great sexual dis- 

 similarity and complete similarity. Instances have already 

 been given with the breeds of the fowl and pigeon, and 

 under nature analogous cases are common. With animals 

 under domestication, but whether in nature I will not ven- 

 ture to say, one sex may lose characters proper to it, and 

 may thus come somewhat to resemble the opposite sex; for 

 instance, the males of some breeds of the fowl have lost 

 their masculine tail-plumes and hacMes. On the other 

 hand, the differences between the sexes may be increased 

 under domestication, as with merino sheep, in which the 

 ewes have lost their horns. Again, characters proper to 

 one sex may suddenly appear in the other sex; as in those 

 sub- breeds of the fowl in which the hens acquire spurs while 

 young; or, as in certain Polish sub- breeds, in which the 

 females, as there is reason to believe, originally acquired 

 a crest, and subsequently transferred it to the males. All 

 these cases are intelligible on the hypothesis of pangenesis; 

 for they depend on the gemmules of certain parts, although 

 present in both sexes, becoming, through the influence of 

 domestication, either dormant or developed in either sex. 



There is one difficult question which it will be convenient 

 to defer to a future chapter, namely, whether a character at 

 first developed in both sexes could, through selection, be 

 limited in its development to one sex alone. If, for in- 

 stance, a breeder observed that some of his pigeons (of 



