Sex Discrimination by Males of the German Cockroach, Blattella germanica (L.) (Orthoptera : Blattidae)

Males of the German cockroach, Blattella germanica(L.), raise their wings when they touch sexually matured females with their antennae. They then secrete a seductive fluid from their tergal gland upon the females. Antennae isolated from the females still possessed such potency as the wing raising of the males.Results of structural observation and biological assays with the antennae indicated that factor(s) responsible for the wing raising is principally not physical, but is of a chemical nature, and this factor is lacalized not only in the antennae of the sexually matured females but also in other organs such as the legs and wings.This factor seemed to be a kind of pheromone brought about by contact chemoreception of the antennae of the male.