Control of oocyte production, development, and release inDrosophila melanogaster.

Sterility in the Hairy-wing 49c mutant ofDrosophila melanogaster is due to the failure of mature oocytes to pass from the oviduct into the uterus.Patterns of oocyte accumulation in the ovaries, oviducts and uterus of mutant and wild-type flies indicate that ovulation is initiated first by mating and thereafter by the absence of an oocyte in the uterus. While oocyte production is also stimulated by mating, it is maintained by a low number of oocytes in the ovary.Mating also appears to initiate events which cause mature oocytes to deteriorate if they are not soon oviposited.