502 



MALE GENITAL ORGANS OF THE OX 



(10 cm.), flanked and overlapped by the vesiculse t-eniinales. They form ampullae 



about four or five inches (10 to 12 cm.) long and half an inch (1.2 to 1.5 cm.) wide, 



the mucous lining of which is plicated. They then pass under the body of the 



prostate and unite with the ducts of the vesiculse seminal es to form the ejaculatory 



ducts. The latter have slit-like openings on either side of the colliculus seminalis 



The vesiculae seminales are not l)ladder-like sacs, as in the horse, but are 



compact glandular organs with a lobulated surface. In the adult they 



measure about four or five inches (ca. 10 to 12 cm.) in length, two inches 



(5 cm.) in width in their largest part, and an inch or more (ca. 3 cm.) in 



thickness. The dorsal surface of each faces upward and inward and is 



The ventral surface faces in the opposite 



direction and is non-peritoneal. Each 



may be regarded as consisting of a 



very thick-walled, sacculated tube, bent 



on itself in a tortuous manner. This 



tube, if straightened out, would be 



about ten inches (25 cm.) in length. 



They are commonly unsymmetrical in 



size and shape. Short branches are 



often given off from the chief tube. 

 Ra-phe 

 glandis 



partially covered with peritoneum. 



Processiis 

 urethrce 



Gnlcn 

 gkmdis 



Raphe 



praputii 

 Prepuce 



Fig. 401. — Anterior Extremity of Penis op Bull, 

 Left View. (After Bohin.) 



Fig. 402. — Cross-section of Pelvic Urethra op 

 Bull. 

 1, Prostate gland (pars disseminata); 2, urethra; 

 3, urethral muscle; 4, aponeurosis. The lumen of the 

 urethra is black. 



The excretory duct or neck joins the outer side of the vas deferens at an acute 

 angle to form the ejaculatory duct. 



The structure of the vesicuhi is masked by a thick capsule of fibrous tissue and unstriped 

 muscle, which maintains it in its bent condition and also sends trabeculse between the alveoli. 

 There is a central canal into wliich the secretion formed in the alveoli passes. The cavities (central 

 canal and alveoli) are lined witli coliunnar epithelium. On account of this structure the term 

 glandulse vesiculares is preferred by some anatomists. 



The prostate is pale yellow in color, and consists of tAvo parts. The body 

 (Corpus prostatte) is a mass which stretches across the dorsal surface of the neck 

 of the bladder and the origin of the urethra. It measures about an inch and a 

 half (ca. 3.5 to 4 cm.) transversely, and about half an inch (ca. 1 to 1.5 cm.) in width 

 and thickness. The pars disseminata surrotmds the pelvic part of the urethra; 

 dorsally it forms a layer about half an inch (ca. 10 to 12 mm.) thick, but ventrally 

 it is quite thin. It is concealed by the urethral (Wilson's) muscle; hence it often 

 escapes notice, but is very evident on cross-section (Fig. 402). The prostatic 

 ducts o\)Qn into the vu'cthra in rows l)etween two folds of the mucous membrane 

 which proceed backward from the colliculus seminalis. 



