76 



TOPOGRAPHICAL ANATOMY OF THE 



with and similar to that over the scrotum. The deep sheet of the 

 parietal layer is thinner and devoid of hairs. The visceral layer of the 

 prepuce is closely adherent to the surface of the peni.s in the region of 

 the glans, and becomes continuous with the mucous lining of the urethra 

 at the external urethral orifice. Behind the glans the visceral layer is 

 looser and generally folded in such a way as to form an inner sheath for 

 the penis ending at a thickened preputial ring (annulus pra-putialis). 

 The degree of development of the inner sheath varies considerably in 

 different individuals. 



To obtain a satisfactory view of the visceral layer of the prepuce, 

 no attempt should be made to withdraw the penis ; but a longitudinal 

 incision should be made through the parietal layer, beginning at the 

 preputial orifice and carrying the cut towards the scrotum. 



Ductus deferens. 



Testis. 



Peritoneum. 



Peritoneum. 



] Testis. 



I I Ductus deferens. 



Fig. 34. — Diagram to illustrate the descent of the testis. 



Dissection. — Before any further examination of the genital organs 

 is attempted, the external pudendal vessels must be followed from the 

 subcutaneous ring of the inguinal canal. Associated with them is a 

 scattered group of superficial lymph glands (lymphoglandulie inguinales 

 superficiales). The dissection is generally rendered tedious by the 

 presence of an accumulation of fat in the inguinal region. 



A. PUDENDA EXTERNA. — The external pudendal^ artery descends 

 the inguinal canal and appears in the present dissection at the medial 

 angle of the subcutaneous ring thereof, in company with the external 

 cremaster muscle. After a short course in a ventral and lateral 

 direction, the artery divides into cranial and caudal branches. The 

 cranial branch, sometimes called the subcutaneous abdominal artery 

 fa. abdominalis subcutanea), runs forwards along the abdominal wall for 

 a considerable distance, its terminal twigs being traceable as far as the 

 umbilicus. Many branches are distributed to the prepuce and the 

 superficial inguinal lymph glands, and one vessel follows the dorsum of 



1 Fudere [L.], to be ashamed ; ■pudendus [L.], of which one ought to be ashamed. 



