452 SPLANCHNOLOGY, OR ANATOMY OF THE VISCERA 



THE PENIS 



The penis consists of a root, a body, and an extremity, or 

 glans penis. 



The body is made up of three cylindrical masses of erectile 

 tissue united together, the two upper of which, lying side by 

 side and called the corpora cavernosa, form the chief bulk 

 of the organ, and the lower, the corpus spongiosum, contains 

 part of the urethra. 



The root is attached to the pubic rami by the crura, and to 

 the symphysis by the suspensory ligament. 



The body is cylindrical when flaccid, triangular with rounded 

 border and sides when erect, the upper side being the dorsum. 

 It is covered by a very thin skin, which is dark in color and 

 devoid of adipose tissue, being loosely connected to the organ. 

 This skin folds upon itself in front to form the prepuce, the 

 under layer of which joins the cervix and becomes very like 

 a mucous membrane, covering the glans and blending into 

 the mucous membrane of the urethra at the meat us. Around 

 the cervix and corona glandis are small glands, the glandule 

 Tysoni odoriferse. 



The glans (see Corpus Spongiosum) is conical and points 

 anteriorly, its summit presenting a vertical slit, the un'nlnx 

 urinarius, from the lower part of which a fold of mucous mem- 

 brane runs back to join the prepuce, and is called the frccnu /// 

 proeputii. The base of the glans projects at its circumference, 

 forming the corona glandis, behind which is a constriction, 

 the cervix. 



The corpora cavernosa are closely connected for the anterior 

 three-fourths, being flattened mesially, while behind they 

 separate, and enlarging at first to form the bulb of the corpus 

 cavernosum, gradually taper, and under the name of crura 

 penis are attached to the rami of the pubes and ischium. In 

 front they form a single blunt extremity, which is joined by 

 fibrous tissue to the base of the glans. Below them is a groove 

 for the corpus spongiosum, and above one for the dorsal vein 

 of the penis. 



The fibrous envelope is composed of longitudinal fibers 

 common to both corpora, and circular fibers which are internal 

 and belong to one corpus only. Mesially, where the circular 



