FEMORAL HERNIA, 293 



project above the pubic bones. The peritoneum is to be detached detach 

 from the inner surface of the flap, and from the iliac fossa. The 

 layer of subperitoneal fatty tissue is to be separated in the same and fat, 

 way. and in doing this the spermatic vessels and vas deferens will 

 come into view as they meet at the internal abdominal ring to form 

 the spermatic cord. Beneath these the external iliac vessels are to and clean 

 be cleaned, with some lymphatic glands lying along them, and the lh 

 genito -crural nerve on the artery. (In the female the round liga- 

 ment of the uterus is seen entering the internal abdominal ring 

 round the epigastric artery ; while the ovarian vessels cross the external 

 iliac trunks above this dissection.) Any loose tissue remaining is 

 to be taken away to show the beginning of the crural sheath around 

 the femoral vessels, and the interval (crural ring) on their inner side 

 (fig. 107). 



Afterwards the trans versalis and iliac fasciae are to be traced to 

 Poupart's ligament, to see the part that each takes in the formation 

 of the crural sheath. 



ANATOMY OP FEMORAL HERNIA. The membranes concerned in Anatomy 

 femoral hernia are the peritoneum, the subperitoneal fatty layer, the structures 

 transversalis and iliac fasciae lining the interior of the abdominal 

 cavity, with the sheath on the femoral vessels to which they give 

 origin at Poupart's ligament. 



The peritoneum lines the inner surface of the abdominal wall, Peritoneal 

 whence it is prolonged without interruption into the iliac fossa and lajer - 

 the pelvis ; and its thinness and weakness are apparent now it is 

 detached. 



The subperitoneal fat extends as a continuous layer beneath the Subperi- 

 peritoneum, but is thickest and most fibrous at the lower part of 

 the abdomen, where the iliac vessels pass under Poupart's ligament. 

 At that spot it extends over the upper opening of the membranous 

 sheath around the vessels, and covers the space of the crural ring 

 internal to the vein. 



The part of this layer which stretches over the crural ring is forms sep- 

 named the septum crnrale ; and a lymphatic gland is generally 

 attached to its under-surface. 



The transversalis fascia has been before noticed (p. 275). At Transver- 

 Poupart's ligament it joins the iliac fascia outside the situation of 

 the external iliac artery ; but internal to that spot it is continued 

 downwards to the thigh in front of the femoral vessels, and forms 

 the anterior part of the crural sheath. 



The iliac fascia covers the ilio-psoas muscle, and lies beneath the Hiac fascia, 

 iliac vessels. At Poupart's ligament it joins the transversalis fascia 

 external to the iliac vessels ; but behind the vessels it is prolonged 

 into the posterior part of the crural sheath. 



The crural sheath is a loose membranous tube, which encloses the Sheath on 

 femoral vessels as they enter the thigh, and is obtained from the 

 fasciae lining the abdomen. Its anterior half is continuous with the 

 transversalis fascia, and its posterior is derived from the iliac fascia 

 and the pubic fascia of the thigh. The sheath is not entirely filled 



