THE ABDOMEN, INTERIOR. 



471 



rests, hence it is called the sustentaculum hepatis. Sim- 

 ilarly, at the point where the transverse colon bends down- 

 ward to form the descending colon, a peritoneal process 

 passes outward to the tenth rib ; 

 this band is the costocolic 

 ligament, or, as the spleen 

 rests upon it, the sustentaculum 

 splenis. 



To return to the foetal con- 

 dition once more, from the front 

 of the small intestine a duct 

 passes off to the yolk sac ; this 

 is the vitello-intestinal duct. 

 Usually this duct becomes 

 entirely obliterated, but some- 

 times it may persist in the adult 

 as Meckel' s diverticulum, usually 

 as a very short, blind tube, from 

 one to three feet from the 

 caecum ; less often does it reach 

 any considerable length, but 

 when it does it may become a 

 menace to the individual from 

 forming adhesions and a portion 

 of the bowel being strangulated 

 by it. 



Peritoneal reflections as seen 

 when the abdomen is opened 



in the adult. The peritoneum is divided, for purposes 

 of description, into various parts, depending upon the loca- 

 tion. The portion of the membrane lining the interior of 

 the abdominal cavity is called the parietal layer, that cover- 

 ing the abdominal organs, the visceral. The peritoneum 



Diag. 38. THE FINAL STAGE IN 

 THE DEVELOPMENT OF THE GREAT 

 OMENTUM. Letters and numbers as 

 in Diag. 36. 



