Female intersexes appeared in two strains of cross breeding in Homoeogryllus japonicus de Haan in 1940. Breeding experiments of this summer, making various combinations with the individuals of that two strains, revealed that this female intersex comes off by a single dominant gene in the autosome. Zygotic females, heterotypic for this gene, are turned to partake male characters and become sterile. On the other hand, this gene has no effect on the zygotic males.