Intersexes in Drosophila Pseudoöbscura

Abstract

Diploid intersexes in D. pseudoobscura are described. Most of them have 2 sets of genital ducts and external genitalia but only 1 pair of gonads. One of the sets of the ducts and the genitalia is almost always more [female]-like and the other more [male]-like. The genetic causation of the intersexuality in this case is most probably a single dominant gene transforming diploid [female][female] into intersexes. The normal allele of this gene need not be regarded as the single gene for maleness nor even as being involved in any way in the mechanism of sex determination.