556 



PERITONEUM. 



this membrane is a shut sac, it is immaterial where we 

 commence tracing it, as we must necessarily return to the 

 place of beginning. If we start at the umbilicus, we fol- 

 low it ascending upon the internal surface of the anterior 

 abdominal walls, to the diaphragm, upon the lower surface 

 of which it is reflected. From the diaphragm it passes on 

 the left side upon the spleen, on the right to the liver, and in 

 the centre upon the stomach. In this course from the um- 

 bilicus there is also a distinct reflection to the convex surface 

 of the liver, called the suspensory or falciform ligament, 

 which receives the ligamentous remains of the umbilical 

 vein. There are other reflections of this membrane upon the 

 liver, which will be noticed in the separate description of this 

 viscus. From the liver, after investing both surfaces, it is 

 traced from the transverse fissure downward to the lesser 

 curvature of the stomach. This reflection is called the lesser 

 omentum, or gastro-liepatic omentum, and encloses the he- 

 patic vessels ; at the lesser curvature of the stomach, the two 

 laminse of this omentum separate, the one to pass in front of, 

 and the other behind the stomach, to meet again along the 

 greater curvature, thus completely investing this organ, ex- 

 cept at the upper and lower curvatures, where this mem- 

 brane separates and again unites. From the greater curv- 

 ature of the stomach, the peritoneum descends to the 

 lower part of the abdomen, and then turning upon itself, 

 ascends to the arch of the colon, thus making this reflec- 

 tion to consist, by its duplication, of four lamina?. It is 

 called the omentum majus, or gastro-colic omentum. 



At the colon it again separates to enclose this intestine, 

 and, upon the concave portion, unites to pass to the spine, 

 forming another reflection, called the transverse mesocolon, 

 which divides the abdominal cavity into two parts supe- 

 rior and inferior. From the spine the transverse mesocolon 

 separates into an ascending and descending portion. The 

 former is traced upward, over the lower part of the duode- 

 num and the pancreas, to the posterior part of the right 

 lobe of the liver, where it is continuous with the perito- 

 neum of this organ, and the posterior layer of the lesser 



