THE ORGANS OF DIGESTION. 



271 



and the rotation of the stomach to the left lead to the pancreas 

 being pressed against the posterior wall of the abdomen on the 

 left side. That part of the dorsal mesogastrium which lies 

 between the stomach and pancreas becomes elongated enormously 

 to form the great omentum, and hence the two anterior layers of 

 the great omentum are attached to the great curvature of the 

 stomach and to the gastro-splenic omentum (Pig. 219). The 

 two posterior layers of the omentum end on the lower (formerly 

 ventral) border of the pancreas. The duodenal loop, with the 

 head of the pancreas in its concavity, is also pressed against 

 the posterior abdominal wall. During all the changes which 

 take place in the position of the pancreas and spleen, owing 

 to the rotation of the stomach and intestine, one structure 

 remains firm, and that is the coeliac axis. The part of the 

 mesogastrium in which the spleen and tail of the pancreas are 

 situated becomes greatly drawn out. Both structures, instead of 

 being situated near the middle line dorsal to the stomach, come to 

 occupy a situation in front of the left kidney, the pancreas thus 



mesogastrium becomes 

 adherent 



spleen 



coeliac axis 

 for. of Winslow. 



hep. art. 

 gastro-hep. om. 



port, vein 



liver 



falciform lig.~ZM 



splenic art. 



mesogastrium 

 (gastro-spl.oment.) 



~ lesser sac 



Fig. 220.— Diagram to show the Formation of the Lesser Sac of the Peritoneum from 

 the Dorsal Mesogastrium. 



coming to lie across, instead of along, the abdominal cavity. The 

 mesogastrium is ballooned out towards the left side to form the 

 lesser sac of the peritoneum, and as the splenic artery lies in the 

 mesogastrium it also is drawn towards the left, circumventing 

 the lesser sac of the peritoneum (Fig. 220). 



