SEX AND SEXUAL CHARACTERS 463 



Seligmann record a case of a male pheasant in which the 

 proximal half of the tail feathers exhibited the female coloration, 

 the distal half the normal markings of the male. The female 

 coloration consists of irregular dark specks on a light-yellowish 

 ground colour between the transverse bars, while in the male 

 part of the feather between the dark bars there is a uniform 

 reddish colour without specks. This looks like the assump- 

 tion of the female character in the latter half of the feather's 

 growth ; but on the other hand, it ma}* be regarded as the 

 absence of the male character. As the bird was not castrated, 

 the former interpretation is the more probable. 



The effects of castration on the male of the domestic fowl 

 are somewhat puzzling, and the evidence of different writers 

 is to some extent contradictory. Shattock and Seligmann state 

 that they have never seen a capon without spurs, even in cases 

 where dissection has shown that no remnant of the testes has 

 been left in the bod} 7 . They also found that the sickle feathers 

 were longer in the capon than in the hen, although not so erect 

 as in the cock. The comb and wattles and the rest of the male 

 plumage were reduced to a condition similar to that of the hen. 

 Darwin, on the other hand, states that the spurs are reduced — 

 which would be expected. Probably the results differ according 

 to the age at which the operation is carried out. There seems 

 no doubt, however, that capons will incubate and hatch chickens 

 and rear them ; and this is evidence against the Mendelian view, 

 for it indicates that the female instincts are latent in the male. 

 Shattock and Seligmann (2) record a case of a cock pheasant not 

 castrated which became broody, drove the sitting hen from a 

 clutch of eggs and sat on them himself. There is then positive 

 evidence of the appearance of female characters in males. It 

 seems to me that in both sexes the result of castration in either 

 sex is usually the suppression of the positive characters of that 

 sex ; but there may be also some slight degree of development 

 of those of the opposite sex, while the marked development 

 of male characters which occasionally occurs in females is 

 exceptional. 



So far as secondary characters are concerned, the fact that 

 those of each sex are latent in the other seems to me to be 

 proved most conclusively by their presence in man}' cases as 

 rudiments. I have already referred to the universal occurrence 

 of rudimentary mammae in male mammals. The transmission 



