FIGURE 6 in On spermatophore-producing aquatic microdrile oligochaetes (Annelida: Clitellata)

FIGURE 6. Smithsonidrilus species (from Smithsonian Institution collection). A. S. marinus marinus Brinkhurst, 1966, copulatory organ. B. S. multiglandularis Erséus, 1990, copulatory glands. C–G. S. marinus marinus: C. Histological section of the male duct. D. Spermathecal duct containing free sperm, and glands associated with the duct. E. Detail of D. F,G. Thecacysts in the spermathecal ampulla, with details of the ectal (F) and ental (G) ends. H,I. S. marinus westoni Erséus, 1990, thecacysts in spermathecal ampulla (H) and detail (I). J. S. multiglandularis, thecacysts in the spermathecal ampulla. Abbreviations: co copulatory organ, ed ejaculatory duct, gl gland, mb male bursa, s sperm, sa spermathecal ampulla, sd spermathecal duct.