. Elements of the comparative anatomy of vertebrates. Anatomy, Comparative. COPULATORY ORGANS 377 seminal tubules become rounded off to form the so-called com vasculosi, and these are connected together by a collecting duct, the vas epididymitis. The vas deferens arises from the last conus yasculosus, and gives rise towards its distal end, shortly before it opens into the urinogenital sinus close to an elevation—the colliculus seminalis, to glandular outgrowths {vesimlm seminahs), which may attain a relatively enormous size in Rodents and In- sectivores (Fig. 299). From this point to its termi
. Elements of the comparative anatomy of vertebrates. Anatomy, Comparative. COPULATORY ORGANS 377 seminal tubules become rounded off to form the so-called com vasculosi, and these are connected together by a collecting duct, the vas epididymitis. The vas deferens arises from the last conus yasculosus, and gives rise towards its distal end, shortly before it opens into the urinogenital sinus close to an elevation—the colliculus seminalis, to glandular outgrowths {vesimlm seminahs), which may attain a relatively enormous size in Rodents and In- sectivores (Fig. 299). From this point to its termination at the. Fig. 300.—Diagrammatic Section of the Testis or a jNIammal. Ho, testis ; NH, ; Vd, vas deferens ; A, albiiginea of the testis, wliich gives rise to the trabeculpe (t, t) and the corpus Highmori (t); L, L, coils of the seminal tubules; Ve, vasa efferentia (rete Halleri) ; Cr, coni vasoulosi, which are connected together by the collecting duct, Vrqi; T'o, vas aberrans. apex of the penis, the seminal canal is spoken of as the ditches ejaculatorius. In many Mammals rudiments of the Miillerian ducts are pre- sent in the male, and open into the urinogenital sinus. In Man, only the most posterior end of the ducts remain in the form of an unpaired vesicle { masculinus), which lies embedded within an accessory genital gland, the2')rostate (Fig. 299). This gland, which more or less completely surrounds the urinogenital sinus, consists of glandular tubules connected together by means of fibrous and muscular tissue : its secretion is poured into the urinogenital sinus, and is apparently of great importance in connection with the activity of the spermatozoa. Copulatory Org^ans. Various forms of copulatory organs, morphologically distinct from one another, occur amongst Vertebrates. In male Elasmo- branchs a specially modified portion of each pelvic fin {clasper or pterygopodiimn, p. 122) serves this purpose. It consists of a series. Please note that the
Size: 1366px × 1828px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectanatomycomparative
