part of adult visceral muscle cell gonadal sheath muscle cell ovarian sheath muscle cell fly_anatomy.ontology FBbt:00003557 Muscle cell of a muscle that is part of the adult ovarian sheath. This is found in the median layer of the sheath, with discontinuous circular muscle found closest to the ovariole and occasional longitudinal fibers in the outer part of the median layer of the sheath (Cummings, 1973). ovarian sheath ovarian sheath cell