part_of part of part of develops_from develops from develops from contributes to morphology of primitive urogenital sinus vagina distal portion of oviduct vaginae A fibromuscular tubular tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles[WP]. distal oviductal region internal female genitalia mesoderm-derived structure subdivision of oviduct