132 HEREDITY AND EUGENICS 



other, while in others the intersexual condition is 

 constant. Juhan Huxle}^ (1922) has discussed this 

 subject. In Drosophila (Bridges, 1921) the sexual 

 condition is shown to depend on a particular balance 

 between the XY chromosomes and the ordinar}^ 

 chromosomes (autosomes), as shown by the fact that 

 triploid individuals receiving only XX chromosomes 

 through non-disjunction are not females but inter- 

 sexes, while triploids with XXX chromosomes are 

 ordinary females. Banta (191 8), from his studies of 

 sex intergrades in Cladocera, concludes that maleness 

 and femaleness are not mutually exclusive states, but 

 that strains representing every quantitative intergrade 

 may be found. Crew (1921) and Witschi (1921)* 

 have shown that in frogs a real transformation from 

 females with ovaries to males occurs, and Crew in his 

 studies obtained the remarkable result that such a 

 transformed female mated with an ordinar}' female 

 produces only females (774 offspring examined in 

 tadpole and frog stage). This is, no doubt, because, 

 notwithstanding the somatic modification of a female 

 to a male, the structure of the germ plasm and the 

 chromosome content (XX chromosomes) remain 

 unchanged. It is not in this direction that any 

 practical application to the human race is to be 

 sought. 



Shattock and Seligman (1906) describe a case of 

 hermaphroditism in a two-year-old Leghorn fowl. 

 The bird laid no eggs and did not crow, but it had 

 the comb, wattles, and spurs of a male, but not its 

 tail feathers. Both male and female genital ducts 

 w^ere present, with an ovotestis on the left side, and 

 apparently a testis on the right side. The authors 



* Swingle (1922) controverts Witschi' s claim to have trans- 

 formed female frogs into males, showing that " appeal to the 

 somatic sex characters completely fails as proof of the trans- 

 iormation of female frogs into males." 



