1014 THE MALE ORGANS OF GENERATION. 



from the superficial layer of the triangular ligament, and is surrounded by the 

 Accelerator urinae muscle. The urethra enters the bulb nearer its upper than its 

 lower surface, being surrounded by a layer of erectile tissue, a thin prolongation 

 of which is continued backward round the membranous and prostatic portions of 

 the canal to the neck of the bladder, lying between the two layers of muscular 

 tissue. The portion of the bulb below the urethra presents a partial division into 

 two lobes, being marked externally by a linear raphe', whilst internally there 

 projects, for a short distance, a thin fibrous septum, which is more distinct in early 

 life. 



Structure. The corpus spongiosum consists of a strong fibrous envelope, 

 enclosing a trabecular structure, which contains in its meshes erectile tissue. The 

 fibrous envelope is thinner, whiter in color, and more elastic than that of the 

 corpora cavernosa. The trabecuhie are more delicate, nearly uniform in size, and 

 the meshes between them smaller than in the corpora cavernosa, their long 

 diameter, for the most part, corresponding with that of the penis. The external 

 envelope or outer coat of the corpus spongiosum is formed partly of unstriped 

 muscular fibre, and a layer of the same tissue immediately surrounds the canal 

 of the urethra. 



The lymphatics of the penis consist of a superficial and deep set ; the former 

 are derived from a dense network on the skin of the glans and prepuce and from 

 the mucous membrane of the urethra, and terminate in the superficial inguinal 

 glands ; the latter emerge from the corpora cavernosa and corpus spongiosum, and, 

 passing beneath the pubic arch, join the deep lymphatics of the pelvis. 



The nerves are derived from the internal pudic nerve and the pelvic plexus. On 

 the glans and bulb some filaments of the cutaneous nerves have Pacinian bodies 

 connected with them, and, according to Krause, many of them terminate in a 

 peculiar form of end-bulb. 



Surgical Anatomy. The penis occasionally requires removal for malignant disease. 

 Usually, removal of the ante-scrqtal portion is all that is necessary, but sometimes it is requisite 

 to remove the whole organ from its attachment to the rami of the ossa pubis and ischia. The 

 former operation is performed either by cutting off the whole of the anterior part of the penis 

 with one sweep of the knife, or, what is better, cutting through the corpora cavernosa from the 

 dorsum, and then separating the corpus spongiosum from them, dividing it at a level nearer the 

 glans penis. The mucous membrane of the urethra is then slit up, and the edges of the flap 

 attached to the external skin, in order to prevent contraction of the orifice, which would other- 

 wise take place. The vessels which require ligature are the two dorsal arteries of the penis, the 

 arteries of the corpora cavernosa, and the artery of the septum. When the entire organ requires 

 removal the patient is placed in the lithotomy position, and an incision is made through the 

 skin and subcutaneous tissue round the root of the penis, and carried down the median line of 

 the scrotum as far as the perineum. The two halves of the scrotum aie then separated from 

 each other, and a catheter having been introduced into the bladder as a guide, the spongy 

 portion of the urethra below the triangular ligament is separated from the corpora cavernosa 

 and divided, the catheter having been withdrawn just behind the bulb. The suspensory liga- 

 ment is now severed, and the crura separated from the bone with a periosteum scraper, and the 

 whole penis removed. The membranous portion of the urethra, which has not been removed, 

 is now to be attached to the skin at the posterior extremity of the incision in the perinaeum. 

 The remainder of the wound is to be brought together, free drainage being provided for. 



THE TESTES AND THEIR COVERINGS (Fig. 565). 



The Testes are two glandular organs, which secrete the semen ; they are sit- 

 uated in the scrotum, being suspended by the spermatic cords. At an early 

 period of foetal life the testes are contained in the abdominal cavity, behind the 

 peritoneum. Before birth they descend to the inguinal canal, along which they 

 pass with the spermatic cord, and, emerging at the external abdominal ring, they 

 descend into the scrotum, becoming invested in their course by numerous coverings 

 derived from the serous, muscular, and fibrous layers of the abdominal parietes, 

 as well as by the scrotum. The coverings of the testes are the 



