PERITONEUM 117 



anteriorly and laterally by the abdominal muscles and iliac 

 bones. The false pelvis is included in the abdominal cavity. 

 The abdomen is divided up into nine regions by two horizontal 

 lines and two vertical lines. 



The subcostal line, the upper of the two horizontal ones, is 

 drawn round the trunk at the level of the lower border of the 

 tenth costal cartilage. The intertubercular line the lower 

 horizontal one is drawn at the level of the tubercles on the 

 crests of the iliac bones, about two inches behind the anterior 

 superior spine. This is the highest point of the iliac crests. 

 The vertical or Poupart's lines are drawn from a point midway 

 between the anterior superior spine of the ilium and the sym- 

 physis of the pubis. 



By this means we have three regions in the middle line the 

 epigastric, umbilical, and hypogastric, and laterally the hypo- 

 chondrium, lumbar, and iliac regions. 



The Peritoneum is a serous sac which lines the abdominal 

 cavity and invests all the structures. It is a thin membrane, 

 secreting sufficient fluid to keep the whole surface lubricated 

 and to enable the organs to move easily over one another. The 

 peritoneum is really one sac, and its arrangement is very com- 

 plicated, as it invests all the organs and connects them with the 

 abdominal wall. 



The connections of the organs to the abdominal wall and to 

 one another are called by three different names : 



Omenta folds of peritoneum connecting the stomach with 

 any other organ. 



Mesenteries folds of peritoneum connecting the intestines 

 with the abdominal wall. 



Ligaments folds of peritoneum connecting organs (not parts 

 of the alimentary canal) to one another or to the abdominal 

 wall. 



Following the peritoneum up the anterior abdominal wall, it 

 passes over the under surface of the diaphragm ; from the pos- 

 terior edge of that it is reflected back over the upper surface of 

 the liver. It then turns round the anterior edge of the liver 

 and, forming the anterior fold of the small omentum, meets the 

 stomach ; it covers the anterior surface of the stomach and hangs 



