File:On the anatomy of vertebrates (electronic resource) (1866) (14568634348).jpg

Identifier: b20416039_002 (find matches)
Title: On the anatomy of vertebrates (electronic resource)
Year: 1866 (1860s)
Authors: Owen, Richard, 1804-1892
Subjects: Anatomy, Comparative Vertebrates Fishes Reptiles Mammals Birds
Publisher: London : Longmans, Green
Contributing Library: Wellcome Library
Digitizing Sponsor: Wellcome Library

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he Common Cock, on a papilla,situated in the urogenital divi-sion of the cloaca anterior tothe insertion of the ureter. The base of each papilla issurrounded by a remarkableplexus of arteries and veins,m, m, fig. 94, which serve as anerectile organ during the vene-real orgasm, when the fossa of theturgid papilla is everted, and thesemen brought into contact withthe similarly everted orifice ofthe oviduct in the female, alongwhich the spermatozoa pass byundulatory movements of theirciliary appendage or e tail. In some Natatores which co-pulate in water there is pro-vision for a more efficient coitusthan by simple contact of evert-ed cloacas, and in the Anatidcea long single penis is developed,fig. 119. It is essentially asaccular production of a highlyvascular part of the lining mem-brane of the cloaca, continuedfrom the fore-part of that cavity,ib. a, a ; and in the passive stateis coiled up like a screw by theelasticity of associated ligamen-The vascular membrane gives off many small
Text Appearing After Image:
Penis of a Drake, xxvn tous structure, b, b. MALE ORGANS OF BIRDS. 245 pointed processes, which, in the Gander, are arranged in transverserows on either side the urethral groove, d, and near the extre-mity of the penis are inclined backward. The elastic band, b, b, hasbeen cut open lengthwise in the figure given by Home:1 it issurrounded by cavernous tissue, and terminates in the blind endof the sac which can be everted. A groove, ib. d, d, commencingwidely at the base, follows the spiral turns of the sac to its termi-nation : the sperm-ducts open upon papilla? at the base of thisgroove. This form of penis has a muscle by which it can beeverted, protruded, and raised. The base of the penis in the Ostrich is attached to the fore wallof the cloaca, the conical body is bent in a recess, out of which itcan be drawn and into which it can be returned by muscles. Itconsists of two solid fibrous bodies, the fissure between which iscovered by cavernous erectile tissue, bounding the seminal gro

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