Elements of comparative anatomy (1878) Elements of comparative anatomy elementsofcompar00gege Year: 1878 188 COMPARATIVE ANATOMY. Each pair of testes lias a seminal vesicle of this kind (Fig. 92, s s''), which is placed across the middle line, and is further provided with lateral diverticula. _k __\ In each of these, two funnel-shaped organs are placed, which are continued laterally into the seminal ducts. The two seminal ducts of either side unite into a common duct (vd)} which extends backwards, and opens laterally on the ventral surface. In the same meta- mere there are two protractile cop
Elements of comparative anatomy (1878) Elements of comparative anatomy elementsofcompar00gege Year: 1878 188 COMPARATIVE ANATOMY. Each pair of testes lias a seminal vesicle of this kind (Fig. 92, s s''), which is placed across the middle line, and is further provided with lateral diverticula. _k __\ In each of these, two funnel-shaped organs are placed, which are continued laterally into the seminal ducts. The two seminal ducts of either side unite into a common duct (vd)} which extends backwards, and opens laterally on the ventral surface. In the same meta- mere there are two protractile copula- Fig. 92. Generative organs of the Earth-Worm. The portion of the body which contains these organs is opened from above, and the walls are laid out on either side. Segments are figiu-ed. n Ventral ganglionic chain, s s' s' Diverticula of the testes, vd Their efferent ducts, o Ovary, ad Ovarian ducts, rs Eeceptaculum seminis (after Hering). tory organs, de- veloped from mo- difications of the setigerous follicles. The ovaries (o) are the smallest organs of the female portion of the generative system. They lie behind the second pair of testes and on each side of the ventral nerve-chord. Behind them two ovi- ducts (ad) are attached to a dissepiment, and begin by two wide abdominal ostia; they pass to the exterior by a short canal placed in the segment in front of the openings of the male organs. Several pairs (generally two) of seminal pouches (receptacula seminis) (rs) are also present. They are large, rounded organs, which lie near the testes, and open by a short duct, without having any close rela- tions to the male apparatus. The paired character of the genital pores, the position of the female one in front of the male, and, finally, the connection between the testes of either side, form an arrangement which, so far as is yet known, has not its like among living allied forms. Even in the Limicola) the organisation is different. The two kinds of generative orga
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