. Elementary text-book of zoology. Zoology. FIG. 292.—Embryo of Echin- orhyncliim gif/n" enclosed in the egg membranes (after Leuckart). and 291, Li). The sexes are s«>i>arate. The male (tig. LMH)) has two testes (T), and the same number of efferent ducts (IV). The latter unite behind to form a ductus fjaculatorius (J)e), which is often fur nislied with .six or eight glandular sacs (TV), and a conical penis (P), at the bottom of a bell-shaped protrusible Imrsa (£), situated at the posterior pole of the body (tig. 2'.H>). The generative organs of the larger females (fig. 291) cons


. Elementary text-book of zoology. Zoology. FIG. 292.—Embryo of Echin- orhyncliim gif/n" enclosed in the egg membranes (after Leuckart). and 291, Li). The sexes are s«>i>arate. The male (tig. LMH)) has two testes (T), and the same number of efferent ducts (IV). The latter unite behind to form a ductus fjaculatorius (J)e), which is often fur nislied with .six or eight glandular sacs (TV), and a conical penis (P), at the bottom of a bell-shaped protrusible Imrsa (£), situated at the posterior pole of the body (tig. 2'.H>). The generative organs of the larger females (fig. 291) consist of the ovary developed in the ligament; of a complicated uterine bell, beginning with a free opening into the body cavity; of the oviduct and the short vagina, which is divided into several portions and opens at the posterior end of the body (tig. 291). It is only in the young stage that the ovary is a simple body en- closed by the membrane of the above-men- tioned ligament. As the animal increases in size, the ovary grows, and becomes divided into numerous spherical masses of eggs, the pressure of which bursts the membrane of the ligament; the ma:->ody cavity into the uterine bell, w h i c h is continually dilating and contracting, thence into the oviduct, and through the genital opening to the exterior. a. FIG. of EchinorJiynehtix jmiteiis from Giiminnr?<s (after Leuckart). a, Free embryo ; Elc, embryonic nucleus. 4, Older stage, with more differentiated embryonic nucleus, c, Young female worm ; Ov, ovary, d, A young male worm ; T, testes; Le, Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Claus, Carl, 1835-1899; Sedgwick, Adam, 1854-1913; Sinclair, F. G. (Frederick Granville), b. 1858. New York : Macmillan


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Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1884