116 



ORIGIN OF SOMATIC 



BARRED FEMALE WITH UNBARRED MALE 

 X 



Barred male. 

 Heterozygous. 



B6 B6 



Unbarred female 

 Homozygous. 



Barred female. 

 Heterozygous. 



Barred male. 

 Heterozygous. 



This case is thus exactly similar to that of Abraxas 

 grossulariata and A. lacticolor. The barred character, 

 like grossulariata^ is dominant, the unbarred recessive, 

 and to explain the results it is necessary to assume 

 that the female is not only heterozygous for the 

 barred character, but also for sex, with the female 

 sex-factor dominant. The recessive character in 

 this case is linked to the female sex-chromosome, 

 or, as Bateson described it, the dominant character is 

 repelled by the female sex-factor. We may make a 

 diagram of the kind given by Morgan if we use a 

 rod of different shape for the female-producing sex- 



