MALE GENITAL ORGANS OF THE OX 503 



The uterus masculinus appears to be absent frequently. Ellenberger 

 states that it o])ens between the ejaeulatory ducts, whih> ]\Iartin says that 

 it usually has two orifices at the coUiculus, but that it often unites with 

 the vasa deferentia. 



The bulbo-urethral (C'owper's) glands are somewhat smaller than in the 

 stallion. They are liable to escape notice, since they are covered by a thick layer 

 of dense fibrous tissue and also partially by the bulbo-cavernosus muscle. Each 

 has a single duct which opens into the urethra under cover of a fold of the mucous 

 membrane. 



The penis is cylindrical, and is longer and of very much smaller diameter 

 than in the horse. Just behind the scrotum it forms an S-shaped curve, the 

 sigmoid flexure ; thus about one foot is folded up when the penis is fully retracted. 

 The flexure is effaced during erection. The glans penis is about three inches (ca. 

 8 cm.) in length. It is flattened dorso-ventrally, and its extremity is pointed and 

 twisted. The external urethral orifice is situated at the end of a groove formed 

 by this twist; it is only large enough to admit a probe of medium size. Even in 

 the non-erect state the penis is remarkably dense and firm. The tunica albuginea 

 is very thick, and incloses the urethra. In the first part, as far as the first curve, 

 there is a thick median septum penis. Beyond this there is a central axial rod of 

 dense fibrous tissue from which numerous strong trabeculae radiate. The erectile 

 tissue is small in amount, so that the organ undergoes very little enlargement in 

 erection. 



The length of the penis in the adult is about three feet (ca. 90 cm.)- The cnu-a are flattened 

 laterally. The suspensory ligaments are attached to the ventral ridge on the symphysis. The 

 body is somewhat flattened dorso-ventrally beyond the first curve. The extremity of the glans 

 is unsymmetrical, the urethral orifice being situated ventro-laterally. The glans contains little 

 erectile tissue, and hence undergoes little enlargement in erection. 



The bulbo-cavernosus muscle presents several remarkable features. It is for 

 the greater part an inch or more (ca. 3 cm.) in thickness, but its length is only 

 six to eight inches (15 to 20 cm.). It is covered by a strong aponeurosis, and is 

 divided by a median raphe into two lateral halves except at its origin. It dim- 

 inishes in size from })ehind forward, and its anterior extremity is pointed. 



The ischio-cavernosus muscle resembles in general that of the horse, but is 

 flattened laterally. It is covered by a close aponeurosis. 



The retractor penis muscle resembles that of the horse in origin. Its two 

 parts are about an inch (ca. 2 to 5 cm.) apart on the root of the penis, where the}' lie 

 in a groove on either side of the bulbo-cavernosus. They then come close together 

 and pass on either side of the ventral curve of the sigmoid flexure. Further 

 forward they lie along the ventral aspect of the penis, and end about five or six 

 inches (ca. 12 to 15 cm.) behind the glans. 



The prepuce is very long and narrow. Its orifice is about two inches (ca. 

 5 cm.) behind the umbilicus; it is only large enough to admit a finger readily, and 

 is surrounded by long hairs. The cavity of the sheath is about fifteen inches 

 (35 to 40 cm.) long, and a little over an inch (ca. 3 cm.) in diameter. The lining 

 membrane forms longitudinal folds; it is covered with squamous stratified epithe- 

 lium, and has coiled tubular glands. The penile layer is glandless, and is reddish 

 in color. It presents lymph nodules in its posterior part. 



There are two pairs of preputial muscles which are derivatives of the pannicu- 

 lus carnosus. The anterior pair, the protractors of the prepuce (Mm. pra'putiales 

 craniales), are two flat bands, two inches or more (5 to 6 cm.) in width, which arise 

 close together in the xiphoid region, about eight inches (20 cm.) in front of the 

 preputial orifice. Traced backward they diverge, leaving the umbilicus and 

 an area about one and a half inches wide free, and then unite behind the preputial 

 orifice. They draw the prepuce forward. The posterior pair, the retractors of 



