Vessels of Penis 425 



cavernosum, but the fibrous trabeculae are connected with the urethral 

 wall instead of with a median septum. The special arteries of the 

 spongy body the arteries of the bulb are derived from the internal 

 pudic trunk, and some branches of the dorsalis penis. 



The dorsal vein begins in small branches, which emerge from the 

 prepuce and glans ; the trunk thus formed lies between the two arteries 

 in the shallow dorsal groove. It receives in its course tributaries from 

 the cavernous and spongy bodies, and, passing beneath the suspensory 

 ligament and through both layers of the triangular ligament, ends in 

 the prostatic plexus. Let this fact be well noted (77. p. 413.) 



Most of the lymphatics end in efferent vessels, which course along 

 the dorsum to end in the inguinal glands ; a deeper set, however, 

 pass beneath the pubic arch to the pelvic glands. A lymphatic gland 

 is occasionally found near the suspensory ligament, where bubo and 

 abscess may occur as a result of a preputial or urethral irritation. 



The nerves are derived from the superficial perineal and the 

 dorsales penis of the internal pudics ; the erectile tissue receiving- 

 additional branches from the hypogastric plexus of the sympathetic. 



Priapism. Under the influence of nervous impressions descend- 

 ing from the brain or spinal cord, or arising in the nerves of the penis 

 itself, or in some offshoot of the recto-vesical network of nerve-tissue, 

 much more blood is brought into the venous sinuses of the trabecular 

 tissue than is able to escape from them ; thus erection of the penis is 

 produced. The efflux is hindered by the expansion from the accelerator 

 urinoe extending over the dorsal vein, and by the erectors of the penis, 

 which compress the crura penis against the side of the pubic arch. 

 Erection may be caused by any local irritation, or by mental stimu- 

 lation acting through the erection centre in the grey matter of the 

 lumbar enlargement of the cord. This, as part of our moral training, 

 should be under cerebral control. When this control is cut off, as in 

 lesions above the lumbar enlargement, from fracture or disease, chronic 

 priapism is apt to occur. 



When suppuration occurs in the body of the penis, the erectile 

 tissue is disorganised and the fibrous cavity distended with pus, which 

 readily makes its way across the pectiniform septum. Similarly, per- 

 sistent priapism may be due to extravasation of blood taking- place 

 during coitus. When suppuration is the cause of priapism, the power 

 of erection may subsequently be lost on account of the destruction of 

 the erectile tissue. 



Forcible flexion of the erect organ may give rise to a species of frac- 

 ture, effusion of blood stiffening the penis and rendering it deformed. 



When the urethra is inflamed, and serous effusion has taken place 

 into the tissue of the corpus spongiosum, a diminution of its elasticity 

 occurs, so that when the penis becomes erect the corpus cavernosum 

 is bent downwards by the sodden and rigid spongy body. The painful 

 condition thus produced is termed chordee (\op8f), bow-string). 



