590 GENITAL ORGANS OF THE BULL 
are about an inch (ca. 2 to 5 em.) apart on the root of the penis, where they 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 for- 
ward they are on the ventral surface of the penis, and end about five or six inches 
(ca. 12 to 15 em.) behind the glans. 
The prepuce is very long and narrow. Its orifice is about two inches (ea. 
5 em.) behind the umbilicus; it is only large enough to admit a finger readily, and 
is surrounded by long hairs. The preputial cavity is about fifteen inches (35 to 40 
em.) long and a little over an inch (ca. 3 cm.) in diameter. The lining membrane 
forms longitudinal folds; it is covered with squamous stratified epithelium, 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 cutaneus 
muscle. The anterior preputial muscles or protractors of the prepuce (Mm. 
preeputiales 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 em.) in 
Processus urethra ‘(/— Processus urethre 
Ja r; 
- 4 9 
Galea glandis — tied 
Galea glandis 
y— Corona glanidis 
Corona glandis — 
P Raphe 
glandis Tuberculum 
Collum glandis 
Collum glandis 
Prepuce 
Prepuce ms 
Raphe preputti 
Fic, 526.—ANTERIOR Part OF PENIS OF RAM. 
A, Right side; B. left side. (After Bohm.) 
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 pre- 
putial orifice. They draw the prepuce forward. The posterior preputial muscles 
or retractors of the prepuce (Mm. prieeputiales caudales) arise in the inguinal region 
and converge on the anterior part of the prepuce. They draw the prepuce back- 
ward.! 
The urethra in its pelvic part is about five inches (12 cm.) long, and is of 
relatively small and uniform caliber. The urethral muscle encloses the tube 
ventrally and laterally; it is very thick, crescentic in cross-section, and is covered 
by an aponeurosis. Dorsally the aponeurosis is thick and the muscle absent. 
Inside of these the pars disseminata of the prostate surrounds the urethra as far 
back as the bulbo-urethral glands. The colliculus seminalis is a rounded promi- 
nence about an inch (ca. 2.5 em.) in length. On it there are two slit-like openings, 
situated close together. These are the ejaculatory orifices, at which the ductus 
deferens and the excretory duct of the vesicula seminalis open. The urethral 
1 These muscles are subject to a good deal of variation. The retractor may be absent. Many 
fibers come in from the cutaneus on either side, dip under the protractor, and are inserted into 
the skin just behind the preputial opening. The homologue of the protractor is present in the 
cow. 
