170 ANATOMY OF THE ABDOMEN, ETC. 



nal abdominal ring. By incising the fascia on the peri- 

 toneum, the handle of a scalpel may be inserted, and 

 pushed down the cord between it and that portion of the 

 transversalis fascia just described as the infundibuliform, 

 showing that at this point the peritoneum might be pro- 

 truded before a knuckle of intestine, and, if forced onward, 

 must pass down in the direction taken by the knife-handle, 

 between the fascia and the cord. The epigastric artery 

 lies between the transversalis fascia and the peritoneum ; it 

 passes under the cord close to the inguinal ring ; the vas 

 deferens hooks over it as it turns downward into the pelvis. 



A large triangular flap of the peritoneum being incised 

 and turned toward the groin, it will be noticed that, upon 

 the median line, there is a cord passing from the bladder 

 'to the linea alba ; this is the remains of the allantois of 

 foetal life ; another cord, being the remains of the oblite- 

 rated hypogastric artery of foetal life, passes obliquely 

 from the umbilicus downward toward the pelvis, in a line 

 nearty corresponding to that of the epigastric artery : this 

 cord, by its shortness, causes the peritoneum to make a 

 pouch on each side these are called the inguinal fossae ; 

 one of them is behind the external ring, and the other 

 behind the internal ring, and it will be seen that each must 

 direct that portion of intestine which accidentally lies within 

 it toward the ring that lies in front of it, and as the abdo- 

 minal wall corresponding to the external ring is weaker 

 than elsewhere, owing to the loss, at that point, of one of 

 the layers constituting its thickness, and at the internal 

 ring, owing to the conformation already described, it fol- 

 lows that a hernia is liable to occur at either situation ; it 

 . is called a direct hernia, if it protrudes from directly oppo- 

 site the external ring, and an oblique hernia, if it enters 

 the internal ring, and follows the direction of the sperma- 

 tic cord. 



By pulling upon the spermatic cord, the peritoneum will 

 exhibit, at the part affected by the traction, a puckered 

 appearance ; this is the point at which that point of the 

 peritoneum, carried before the testicle in its descent to the 

 scrotum, is obliterated from its connection with the general 

 cavity. The portion of peritoneum intervening between 

 this point and the scrotum, usually degenerates into cellu- 

 lar tissue ; it ma}^, however, remain as a distinct cord, or 

 even as a pervious tube. In the female subject, the round 

 ligament enters the internal ring in place of the spermatic 



