Text-book of comparative anatomy . ic in their arrangement, in cor-respondence with the more or less regular metameric arrangementof the enteric diverticula themselves. In some Nemertina there arealso genital glands scattered about the parenchyma, each gland, however,has an independent external aperture. In this arrangement we findgreat agreement with the Turbellaria (especially the Polyclada andTriclada). In the latter, however, the oviducts and sperm ductsarising from the genital glands unite to form common channels of exit. Nemathelminths.—1. Nematoda.—The male genital apparatus isunpaired,
Text-book of comparative anatomy . ic in their arrangement, in cor-respondence with the more or less regular metameric arrangementof the enteric diverticula themselves. In some Nemertina there arealso genital glands scattered about the parenchyma, each gland, however,has an independent external aperture. In this arrangement we findgreat agreement with the Turbellaria (especially the Polyclada andTriclada). In the latter, however, the oviducts and sperm ductsarising from the genital glands unite to form common channels of exit. Nemathelminths.—1. Nematoda.—The male genital apparatus isunpaired, and emerges at the posterior end of the body in the cloaca;the female apparatus is paired, and emerges externally on the ventral IV VERMES—GENITAL ORGANS 255 side in front of the anus, generally near the middle of the body. Themale genital apparatus (Fig. 168) is a single continuous tube,lying in the body cavity, which falls into several divisions betweenits blind inner end and its external aperture. The testicle division k. FIG. 168.—Ascaris lumbricoides,male genital apparatus, after Vogtand Yung, sf, Lateral lines; /(,testes ; d, intestine ; sb, sperm vesi-cle ; U, cloaca; de, ductus ejacula-torius.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectanatomycomparative
