ABDOMINAL CAVITY 



455 



rib in the mid-axillary line. On the right side the dividing 

 fold is placed much lower and is frequently less distinct. 

 It passes from the side wall of the abdomen, in the upper 

 part of the iliac region, to the lateral wall of the lower part of 

 the ascending colon. The lateral gutters and the folds 

 which divide them are of importance because they tend 

 to localise abnormal collections of blood or inflammatory 



FIG. 174. Transverse section of Abdomen through the fourth lumbar 

 vertebrae. 



1. Small intestine. 



2. Great omentum and omental bursa. 



3. Descending colon. 



4. Aorta. 



5. Inferior vena cava. 



6. Ascending colon. 



7. Great sac. 



8. Omental bursa (O.T. small sac). 



9. Great sac. 

 10. Mesentery. 



effusions which may be in the cavity of the great sac, and 

 the dissector should note that in the recumbent posture 

 the lowest part of each lateral gutter is situated at the level 

 of the upper part of the kidney in the region of the last 

 intercostal space. 



The upper portion of the posterior part of the cavity of the 

 great sac, the part behind the greater omentum, is also divided, 

 in the upper part of its extent, into lateral parts, by the 

 mesentery of the small intestine, which runs obliquely from the 

 left side of the second lumbar vertebra to the right iliac fossa. 



