COURTSHIP AND SEX 223 



tion ? The reindeer is the only deer with antlers in the 

 female as well as in the male. Is this a case of the extension 

 of an originally masculine character to the female, or does it 

 illustrate Tandler's theory — that antlers primarily occurred 

 in small measure on both sexes, but were gradually sup- 

 pressed (with the single exception of the reindeer) in the 

 female, and exaggerated in the male ? It remains a question 

 of interpretation. 



In the peacock-pheasants (Polyplectron) some of the 

 species have plain-coloured females, but in the other species 

 there is an approach to the male splendour. In one of the 

 wild- turkeys {Meleagris ocellata) the decorative " eyes " on 

 the tail occur in both sexes. There are not a few of these 

 cases, but it seems difficult to decide whether species- 

 characters are becoming somewhat divergent sex-characters, 

 or whether a character primarily masculine is becoming a 

 species-character of both sexes. 



The syrinx or song-box may be regarded as a possession 

 of both sexes, but it often attains to a much stronger and 

 more complex development in the male bird. Thus among 

 ducks the males often show a special enlargement or re- 

 sonating sac, and Meisenheimer (1921, p. 738) calls attention 

 to the fact that a female Australian widgeon {Mareca punctata) 

 is unique in showing in the adult an approximation to what 

 occurs in the male. He regards this as the beginning of an 

 extension of a masculine character to the female, and gives 

 as another example the incipient coiling of the windpipe in 

 some females. It is coiled round several times in many 

 males. 



Suggested Theory o£ the Mode of Origin of Sex-Characters. 

 — If we turn aside from the hypothesis that sex-characters 

 arose by the hereditary accumulation of the direct 

 results of somatic modifications, whether functional or 

 environmental, we are led to conclude that they arose as 

 germinal variations or mutations. That the germinal origin 

 of variations or of mutations is wrapped in obscurity makes 

 all phylogenetic aetiology difficult ; there is no special 

 difficulty in regard to sex-characters ; the problem of 



