Fig. 3. Meiotic maturation and ovulation. (A-C) Three sequential Nomarski DIC micrographs showing normal meiotic maturation, ovulation and sperm-oocyte contact in a spe-38(eb44) hermaphrodite. The black arrows indicate the position of the same oocyte as it moves from the oviduct (A) to the spermatheca (site of sperm storage; B) and finally to the uterus (C). The oocyte spent 7 minutes in contact with sperm in the spermatheca without being fertilized. The uterus is filled with previously unfertilized oocytes. (D) A wild-type hermaphrodite has a uterus that is filled with developing embryos. Unlike unfertilized oocytes, developing embryos are oval and are enclosed within a clearly defined eggshell. In all panels, the white arrows indicate examples of sperm and their position.