. Outlines of zoology. Fig. 209.—Dissection of snail. T., Short horn; TT.^ long horn with eye; N,, cerebral ganglia; ,salivary glands on the crop; i?., foot; M., columellar muscle; ,visceral coil; d^.T., ovotestis ; F., ventricle of heart; i?. rectum ; £/.,ureter; ^.K., bloo^ vessels returning to the auricle from the mantle;A., pulmonary aperture; MA., edge of the mantle. less prominent groove, incompletely separated from theother. Both paths are glandular, and the glands on themale side are often called prostatic. (e) At the base of this common duct, a distinct vasdeferens diverges
. Outlines of zoology. Fig. 209.—Dissection of snail. T., Short horn; TT.^ long horn with eye; N,, cerebral ganglia; ,salivary glands on the crop; i?., foot; M., columellar muscle; ,visceral coil; d^.T., ovotestis ; F., ventricle of heart; i?. rectum ; £/.,ureter; ^.K., bloo^ vessels returning to the auricle from the mantle;A., pulmonary aperture; MA., edge of the mantle. less prominent groove, incompletely separated from theother. Both paths are glandular, and the glands on themale side are often called prostatic. (e) At the base of this common duct, a distinct vasdeferens diverges to the left and leads into a muscular/e««j-, 39° PHYLUM MOLLUSC A. which can be protruded at the single genital aperture andretracted by a special muscle. Before the vas deferensenters the penis, a long process or flagellum is given is like the lash of a whip, and is as long as the commonduct. Its secretion is used in forming a sperm-packet orspermatophore of a large number of spermatozoa, which are. Fio. 210.—Reproductive organs oi Helix pomatia.—After Meisenheimer. O. T., Ovotestis ; H, hermaphrodite duct; , albumen gland ; ^female side of common duct; , male side of common duct; O.,oviduct; receptaculum seminis; , mucus glands; ,dart-sac; , vas deferens; i^i.,flagellum; P.,penis; AT,,retractormuscle of penis ; AP., genital aperture. compacted together at the time of sexual union partly inthe flagellum, partly in the penis. The spermatophore istransferred by the penis into the genital aperture of anothersnail. (/) Continued from the oviducal side of the commonduct, there is a separate ciliated oviduct. This has a shortcourse, and ends in the common genital aperture. Before REPRODUCTIVE SYSTEM. 391 it reaches this, however, the oviduct is associated with twostructures. The first of these is a long process, as long asthe common duct beside which it runs, in appearancesuggesting the flagellum, but expanding at its free end into
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Keywords: ., bookcentury1900, bookdecade1910, bookidcu3192, booksubjectzoology
