DIGESTIVE SYSTEM. 



Great Sac. The anterior layer lines the anterior abdominal 

 wall. Superiorly it forms a crescentic fold (falciform ligament) , 

 just to the right of the midline, running to the parietal surface 

 of the liver and enclosing the round ligament. Inferiorly it 

 forms folds over five structures descending from the umbilicus, 

 viz. : the urachus mesially and the deep epigastric and oblit- 

 erated hypogastric arteries on each side. Three inguinal /ossce 

 are formed on each side by these folds, viz. : one (external) out- 

 side the deep epigastric artery, over the internal abdominal 

 ring; one (middle) between the arteries; and one (internal) 

 between the obliterated hypogastric artery and the urachus. 

 Under the inner end of Poupart's ligament, over the crural 

 ring, is another (femoral, or crural fossa} . [1097] 



The posterior layer, when traced vertically in the midline, 

 runs from the diaphragm to (upper layer of coronary ligament) 

 the liver and over the parietal and then the visceral surface to 

 the portal fissure. Thence it descends (anterior layer of lesser 

 omentum) to the lesser curvature of the stomach, and runs 

 over the upper surface to the greater curvature. It descends 

 thence as the anterior layer of the great omentum ; then, bend- 

 ing on itself, it ascends as the posterior layer to the transverse 

 colon, covers the posterior surface of this and passes (posterior 

 layer of transverse mesocolon) to the anterior border of the 

 pancreas. Thence it covers the inferior surface of the pancreas 

 and descends along the posterior abdominal wall, running for- 

 ward around the small intestine and back again to form the 

 mesentery, to the pelvis. [1099] 



Then descending into the pelvis (pelvic peritoneum) it covers 

 the pelvic colon completely, forming the pelvic mesocolon, 

 and then partly covers the upper two-thirds of the rectum. 

 From the front of the rectum it passes, on each side, to the 

 posterior pelvic wall, forming the bottom of a large fossa (para- 

 rectal) seen at the sides of the rectum when empty. It also 

 passes forward from the rectum in two folds (in the male), be- 

 tween which is the recto- vesical pouch, to the back of the blad- 



[227] 



