. Elementary text-book of zoology, general part and special part: protozoa to insecta. Animals. ACANTHOCEPIIALA. 361. FiQ. 292.—Embryo of Echin- orhynchiig g'<j(i» enclosed in the egg membranes (after Leuckart). and 291, Li). The sexes are separate. The male (fi<,'. 290) has two testes {T), and the same nvimber of efferent dvicts {Vd). The latter unite behind to form a ductus ejaculatorius {Be), which is often fur- nished with six or eiglit ghindular sacs {Fr), and a conical penis (P), at the bottom of a bell-shaped protrusible bursa (B), situated at the posterior pole of the body (fig.
. Elementary text-book of zoology, general part and special part: protozoa to insecta. Animals. ACANTHOCEPIIALA. 361. FiQ. 292.—Embryo of Echin- orhynchiig g'<j(i» enclosed in the egg membranes (after Leuckart). and 291, Li). The sexes are separate. The male (fi<,'. 290) has two testes {T), and the same nvimber of efferent dvicts {Vd). The latter unite behind to form a ductus ejaculatorius {Be), which is often fur- nished with six or eiglit ghindular sacs {Fr), and a conical penis (P), at the bottom of a bell-shaped protrusible bursa (B), situated at the posterior pole of the body (fig. 290). 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 (fig. 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 masses of ova as well as the i-ipe elliptical eggs, which gradually become free from them, fall into the body cavity. The ^^^^^ membranes are not formed till ^ ^ '^ — after seg- mentation, and ought perhapsto be interpreted as embryo- nic mem- branes. The eggs, which already con- tain em- bryos, pa^s out of the body cavity into the uterine bell, which is continually dilating and contracting, thence into the oviduct, and through the genital opening to the 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; Metcalf Collection (North Carolina State University). NCRS.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectanimals, bookyear1892
