. Comparative anatomy of vertebrates. Anatomy, Comparative; Vertebrates -- Anatomy. UROGENITAL SYSTEM. 323 the longitudinal testicular canal of other vertebrates) which runs in the membrane (mesorchium) supporting the testis, back to the external opening, which is either directly to the exterior between the urinary opening and the anus (fig. 328) or into a urogenital sinus (fig. 321, B). This view is farther supported by the relations in the dipnoi. In Ceratodus there are numerous vasa efferentia which extend from the testis into the mesonephros. In Lepidosiren the efferent ductules are. FIG.
. Comparative anatomy of vertebrates. Anatomy, Comparative; Vertebrates -- Anatomy. UROGENITAL SYSTEM. 323 the longitudinal testicular canal of other vertebrates) which runs in the membrane (mesorchium) supporting the testis, back to the external opening, which is either directly to the exterior between the urinary opening and the anus (fig. 328) or into a urogenital sinus (fig. 321, B). This view is farther supported by the relations in the dipnoi. In Ceratodus there are numerous vasa efferentia which extend from the testis into the mesonephros. In Lepidosiren the efferent ductules are. FIG. 325.—Diagrams of urogenital organs of male fishes, after Goodrich. A, Acipenser (Lepidosteus and Amia similar, but lack the oviduct); B, teleosts; C, Polypterus; D, Pro- topterus; E, urogenital openings of female salmon, a, anus; ap, abdominal pore; cb, cloacal ('urinary') bladder; e, vasa efferentia; gp, genital pore (papilla); m, mesonephros; md, Mullerian(?) duct; r, rectum; re, renal corpuscle; s, urogenital sinus; /, testis; u, up, urinary pore; ugp, urogenital pore; v, vas deferens; w, Wolffian duct. fewer in number and they arise from a posterior degenerate portion of the testis, while in Protoptems (fig. 325, D] there is but a single vas efferens on either side and this passes through the posterior end of the Wolffian body. Oviducts.—In the elasmobranchs the Miillerian duct, which, as described above, arises by a splitting of the pronephric duct, serves as the oviduct. After separation from the Wolffian duct this opens in front into the ccelom by means of the pronephric tubules and their. 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 Kingsley, J. S. (John Sterling), 1854-1929. Philadelphia, P. Blakiston's son & co.
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectanatomy, bookyear1912
