; THE PENIS. 1115 
Kach corpus cavernosum ends ina blunt conical extremity, the apex of which is 
received into a hollow in the base of the glans. The skin covering the body of the 
penis is thin, delicate, and freely movable, and, except near the root of the organ, 
is free from hairs. On the urethral aspect of the penis the skin is marked by a 
median raphe, continuous with the raphe of the scrotum. Reaching the base of 
the glans, the skin forms a free fold called the prepuce (preeputium), which overlaps 
the glans to a variable extent. From the deep surface of the prepuce the skin is 
reflected on to the terminal part of the penis, just above the level of the corona 
glandis, and is continued over the entire glans to the meatus urinarius. A small 
fold, the frenulum preputii, passes to the deep surface of the prepuce from a point 
just below the meatus urinarius. The skin covering the glans is firmly attached 
to the underlying erectile tissue, and here, as well as on the deep surface of the 
prepuce, it presents some resemblance to mucous membrane. 
Minute sebaceous glands (glandulze preeputiales) are found on the glans and inner 
surface of the prepuce; the secretion from these helps to form the smegma preputii, 
which tends to collect in the groove between the glans and the prepuce. 
At the root of the penis (radix penis) the three component parts of the organ 
separate from one another (Fig. 761). The corpora cavernosa, diverging from each 
other laterally, at first become somewhat swollen, and then gradually tapering off, 
gain a fibrous attachment to the inner part of the pubic arch. These diverging 
parts of the corpora cavernosa are called the crura penis, and each is covered by the 
corresponding ischio-cavernosus muscle. The corpus spongiosum lying between 
the crura becomes enlarged, and forms a somewhat spherical mass which receives 
the name bulb of the urethra (bulbus urethre). The bulb varies much in size 
in different individuals, and is attached to the under surface of the triangular 
ligament, against which it rests. The posterior part and under surface of the 
bulb usually show a median notch or groove, which is an indication that the bulb 
is originally composed of two symmetrical portions, fused in the middle line. 
These two portions are termed the hemispheria bulbi urethre, and are best seen in 
subjects whose tissues have been hardened by intra-vascular injections. Covering 
the superficial surface of the bulb is the bulbo-cavernosus muscle. The canal of 
the urethra, piercing the triangular ligament, enters the bulb a short distance in 
front of its posterior extremity (Fig. 765). 
A somewhat triangular band of strong fibrous tissue, called the suspensory 
ligament of the penis, is 
attached to the front of 
the symphysis pubis, and 
extends to the fibrous cap- 
sule of the penis, with 
which it becomes con- 
tinuous (Fig. 759). 
Structure of the 
Penis.—Each corpus caver- 
nosum penis is enclosed by 
a dense fibrous coat or tunica fic. 762.—A LoNGITUDINAL SECTION OF THE TERMINAL PoRTION OF 
albuginea (tunica albuginea . THE PENIS, AND A TRANSVERSE SECTION THROUGH THE Boby OF 
corporum cavernosorum), Saas ORGAN. ae pers nt 
which, fusing with the corre- a. Corpus cavernosum. ¢ G ans penis, _ g oree Ds MY 
s 2 ft] : b. Corpus spongiosum.  e. Fossa navicularis. h. Dorsal artery. 
sponding coat of the opposite ~ Uyethral canal. f, Part of septum pectiniforme. 7. Dorsal nerve. 
side, forms a mesial septum 
(septum penis). The septum is very incomplete, especially near the terminal part of the 
penis, where it is interrupted by a number of nearly parallel slit-like perforations, hence 
the term septum pectiniforme is often applied to it. ‘Through these openings the erectile 
tissue of the corpora cavernosa of opposite sides is continuous. 
The fibrous coat contains many elastic fibres, and may be divided into an outer layer 
of longitudinally directed fibres and an inner layer of circular fibres, some of which latter 
are continued into the septum. Numerous fibrous strands, called trabecule (trabeculee 
corporum cavernosorum), proceed from the deep surface of the tunica albuginea, and 
stretching across the interior of the corpus cavernosum, form a fine sponge-like framework 
