. The elasmobranch fishes . Fig. 254. Urogenital system of male. A. Sqnatina. B. L'aja. (From Borcea.) , central canal of testis; ct., collecting tube; led., kidney; , median vesicle; nph., nephrostome; sc, sperm sac; , segmental duct; , vesicula seminalis; t., testis; «., ureter; ug., urogenital sinus; , vas deferens; , vas efferens. probably because of pressure from the digestive organs, becomes divided into widely separated parts. DUCTS OF KIDNEY In a type like Sqimiina (see male, fig. 254a) the collecting tubules {ct.) which drain the anterior part of the kidney emp
. The elasmobranch fishes . Fig. 254. Urogenital system of male. A. Sqnatina. B. L'aja. (From Borcea.) , central canal of testis; ct., collecting tube; led., kidney; , median vesicle; nph., nephrostome; sc, sperm sac; , segmental duct; , vesicula seminalis; t., testis; «., ureter; ug., urogenital sinus; , vas deferens; , vas efferens. probably because of pressure from the digestive organs, becomes divided into widely separated parts. DUCTS OF KIDNEY In a type like Sqimiina (see male, fig. 254a) the collecting tubules {ct.) which drain the anterior part of the kidney empty directly into the Wolffian duct, and those of the posterior part join a ureter (?<.). This is essentially the con- dition in Heptanchus, except that in Heptanchus the ureter is of immense size. In Scyllium (see p. 189, fig. 177a) the Wolffian duct is terminated by an enlarged portion, the urinary vesicle (), and the collecting tubules in the posterior part of the kidney are dispersed at their termini, several of them joining to form a diminutive ureter only at the place where they empty into the urinary sinus. A modification of this plan is met with in the rays in
Size: 1526px × 3275px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookpublisherberkeleycalifuniversityofcaliforn
