176 SURGICAL ANATOMY OF 



fascia. It is the weakness or giving way of these bands 

 which favors the hernial protrusion. The inner pillar 

 of the ring is flat and riband-shaped, whilst the outer is 

 sickle-shaped and thick, and upon it the cord or round 

 ligament rests. On detaching a " dog's ear" of the apo- 

 neurosis of the external oblique along Poupart's ligament, 

 immediately beneath it is a cellular interval separating 

 it from the muscular fibres of the internal oblique, and 

 the conjoined tendon of this muscle and the transversa- 

 lis, this latter passing in front of the rectus and pyrami- 

 dalis to the linea alba and pubes ; blended with the lower 

 fibres of the internal oblique and transversalis are the 

 fibres of the cremaster muscle, on which the ilio-ingui- 

 nal nerve lies. On carefully detaching the muscular 

 fibres of the internal oblique from Poupart's ligament, 

 and reflecting them outwards and inwards, the fibres of 

 the transversalis are met with, forming an arch over the 

 cord, and beneath this arch is the spout-like prolonga- 

 tion of the transversalis fascia (the infundibuliform) in- 

 vesting it. Behind the transversalis and the rectus, is 

 the transversalis fascia, closely lining them, and here 

 forming with the subperitoneal aponeurosis the posterior 

 layer of the sheath of the latter muscle ; in its lower 

 fourth it is attached to the under surface of the crural 

 arch, becoming continuous with the fascia iliaca. Be- 

 neath this fascia is the parietal layer of the peritoneum. 



The position of the deep epigastric vessels can be easily 

 seen, lying beneath the transversalis fascia and the peri- 

 toneum, and passing obliquely upwards and inwards, to 

 gain the under surface of the rectus at about its lower 

 third and internal to the cord. 



It will be now found convenient to turn down the flap 

 consisting of the entire thickness of the abdominal wall 



