1388 CLINICAL AND TOPOGRAPHICAL ANATOMY 



only the upper part perists, and does not communicate with the ttmica vaginalis, it is called a 

 funicular sac. Cysts originating in the processus vaginalis between the upper and lower 

 points of primary occlusion are known as eyicysted hydrocele of the cord. 



Undescended testis. — It occasionally happens that descent of the testis fails on one or 

 both sides, and in these cases the organ may remain, (1) in the iliac fossa, (2) in the inguinal 

 canal, or (3) at the subcutaneous ring. Deprived of the protection normally afforded against 

 injury by the scrotum and tunica vaginalis, the misplaced testis is subject to trauma, shows a 

 tendency to torsion of its pedicle owing to its long mesorchium, and sometimes becomes the 

 seat of malignant disease. A funicular hernial sac is generally present. Such testes are atro- 

 phic and functionally deficient, and it is probably owing to their small size at an early stage that 

 the gubernaculum fails to gain a hold on them. It has been shown by Bevan* that in unde- 

 scended testis the ductus deferens is usually long enough to allow the organ to be placed in the 

 bottom of the scrotum by the surgeon without tension provided that the spermatic artery and 

 pampiniform plexus of veins are divided. The blood-supply of the organ is then entirely 

 derived from the deferential artery, a branch of the superior vesical. In rare cases the testis 

 descends in a wrong direction (ectopia testis) and comes to lie in the perineum, over Scarpa's 

 triangle, or on the pubes. 



Penis. — The subcutaneous tissue of the penis, as on the scrotum, is devoid 

 of fat and the delicate skin is very mobile and distensible, hence the ballooning 

 of these parts in extravasation of urine or oedema. The fascia penis is continuous 

 with CoUes's fascia. 



In radical amputation of the penis for malignant disease the whole organ, including the 

 crura, is removed through an incision that splits the scrotum, and the stump of the corpus 

 spongiosum (corpus cavernosum urethrse) is brought out into the perineum behind the scrotum. 



The preputial orifice varies greatly in size. Normally large enough to allow easy retrac- 



FiG. 1117. — Cross-section op Penis. 



Superficial dorsal vein of penis 

 Dorsal artery y^ I /Deep dorsal vein 



Tunica albuginea _ZJ|;^*^^IS^»§^1-^^ Septum 



Vessels 



Tunica albuginea- 



Skin 

 Dartos 



—Corpus cavernosum penis 

 Fibrous sheath of penis 



Artery 



Artery 



Urethra 

 Corpus cavernosum urethrae (spongiosum) 



tion of the prepuce from off the glans, it is frequently so small that retraction is impossible 

 and it may even cause difficulty in micturition. The mobility of the skin over the penis must 

 be borne in mind in the operation of circumcision, and care taken lest too much of the prepuce 

 be reinoved, leaving insufficient skin to cover the penis. In this operation the vessels from which 

 bleeding occurs lie, (1) on the dorsum, (2) in the frenum. 



Congenital malformations of penis. — At an early stage of development the urethra opens 

 on the inferior aspect of the penis behind the glans. After the ingrowth of epithelium that 

 forms the glandular urethra, this primitive meatus should close. Occasionally, however, it 



fcrsists, and the glandular urethra is roproscntod by a groove on the under aspect of the glans. 

 n these cases of hypospadias the glans is flexed on the penis and the prepuce is deficient below 

 and has a peculiar "hooded" appearance. In epispadias the upper wall of the urethra and 

 corresponding part of the corpora cavernosa are absent. This condition is usually present 

 in cases of ectopia vesicai. 



The male urethra is about 20 cm. (8 in.) in length, consisting of the cavernous 

 portion, 16 era. (6^ in.), membranous 1 cm. (| in.) and prostatic 3 cm. (Ij in.). 

 The narrowest part is the external orifice, and next to it the membranous 

 urethra. The prostatic urethra is the Avidest and most dilatable. The bulbous 

 urethra, just in front of the uro-genital diaphragm, is wider than the rest of the 

 penile portion, but since it forms the most dependent spot in the fixed part of 

 the urethra (from bladder to suspensory ligament of penis), it is specially prone 

 to gonorrha-al stricture. Behind the bulb, the urethra narrows suddenly as it 

 passes through the uro-genital diaphragm and contraction of the sphincters of 



* Journ. Amer. Med. Assoc, vol. 41, 1903, p. 718. 



