THE GENETICS OF HABROBRACON JUGLANDIS ASHMEAD 



the female. Like gynoid, these intersexes dif- 

 fer from sex mosaics in being approximately sym- 

 metrical and similar to each other. They pos- 

 sess intermediate sex characters and occur in a 

 group in one fraternity as if caused by a sin- 

 gle hereditary factor. 



The existing data must be regarded as inade- 

 quate to prove whether these intersexes are the 

 result of a modification of the normal sex-dif- 

 ferentiating factor or whether, like gynoid, 

 they are the result of an independent change. 

 It is questionable whether the diverse effects 

 of gynoid antennae and abdominal sclerotization 

 should be regarded as multiple effects of a sin- 

 gle gene. Gynoid may possibly be a transloca- 

 tion from the differential segment determining 

 sex. In a male with the sex allele in the nor- 

 mal position this might give a complementary 

 feminizing effect causing intersexuality . 



Mosaics also occur which apparently possess 

 either one sex or the other; however, these too 

 exhibit interesting peculiarities. Genetic ev- 

 idence indicates that mosaics, v;ith but few ex- 

 ceptions, arise from binucleate eggs. The two 

 nuclei are assumed to be the products of the 

 second oocyte division. In the case of gynan- 

 ders one of the nuclei is fertilized and gives 

 rise to the female parts while the unfertilized 

 nucleus produces the male parts. Cell descend- 

 ants of each of the two nuclei tend to be more 

 or less segregated in different regions of the 

 embryonic syncytium and consequently the genet- 

 ically diverse regions may be roughly separated 

 by a plane. This plane of division may appar- 

 ently lie at any angle to the axis of the body 

 and may separate proportions varying from ap- 



