The Cambridge natural history . the hei-mapliroditc gland or ovo-testis (), a yellowishwhite mass of irregular shape, embedded in the liver (l.) andforming part of its spiral but not reaching quite to the this gland are developed the ova and spermatozoa. Theformer are rather large round cells, produced within the outerwall of the gland, while the spermatozoa, which are produced inthe more central part, are threadlike bodies, generally aggre-gated in small bundles. From the hermaphrodite gland the ova1 Steenstrup, Ann. Mag. Nat. Hid. (2), xx. p. 81 f. GENERATIVE ORGANS OF HELIX
The Cambridge natural history . the hei-mapliroditc gland or ovo-testis (), a yellowishwhite mass of irregular shape, embedded in the liver (l.) andforming part of its spiral but not reaching quite to the this gland are developed the ova and spermatozoa. Theformer are rather large round cells, produced within the outerwall of the gland, while the spermatozoa, which are produced inthe more central part, are threadlike bodies, generally aggre-gated in small bundles. From the hermaphrodite gland the ova1 Steenstrup, Ann. Mag. Nat. Hid. (2), xx. p. 81 f. GENERATIVE ORGANS OF HELIX 141 and spermatozoa pass through the upper part of the licrmcqiliroditeduct (), which is always more or less convoluted. Belowthe convoluted portion, the duct opens into the alhumcn gland(), a large linguiforin mass of tissue which becomes dilatedat the time of pairing, and secretes a thick viscid iluid whichprobably serves to envelop the ova. Up to this point boththe male and female elements follow the same course, but. Fig. —Genitalia of Helix aspersaMiiller, drawn from two indivi-duals iu the act of union, from adissection by F. B. Stead. A. G, albumen gland. C, caecum, Cr, crop. , dart sac. E, eye (retracted) Fl, tiagellum. , liermaplirodite duct. , ditto, female portion. , ditto, male portion. , licrmapbrodite gland. L, liver. , , mucous glands. Ov, oviduct. , penis sac. , retractor muscle of jienis. Sp, spermatbeca. V, vagina. , vas deferens. on tlieir exit from the albumen gland they diverge. The herma-phrodite duct becomes greatly enlarged, and is partially dividedby a kind of septum into a male and female portion. These runparallel to one another, the larger or female portion (ildf.),through which the ova pass (and which is sometimes termed theutems) being dilated into a number of puckered folds, while thesmaller or male portion () is comparatively narrow, andnot dilated. At their anterior end, the two portions of the
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
