Ultrastructural observations of ovulation in the Japanese long-fingered bat, Miniopterus schreibersii fuliginosus.

In the Japanese long-fingered bat, Miniopterus schreibersii fuliginosus, ovulation occurred spontaneously with the disappearance of the granulosa layer and germinal epithelium at the apex of the stigma which was formed simultaneously with expulsion of the first polar body, and with the subsequent bleeding from the capillary lumina of the theca interna. After ovulation the rupture point was plugged by luteinizing granulosa cells and overgrown by newly regenerated cells of the tunica albuginea and germinal epithelium.