PERITONEUM. 



103 



- Fig. 84. 



of the abdomen, and covering 

 most of the viscera that are 

 contained therein ; it is a se- 

 rous membrane, and there- 

 fore a shut sac, following the 

 general rule of lining the 

 cavity, and covering the or- 

 gans contained within. It se- 

 cretes a small quantity of 

 fluid in health, which lubri- 

 cates the surfaces of the vis- 

 cera, so that they readily 

 move upon each other and 

 the walls of the cavity. It 

 also forms ligaments and con- 

 nexions whereby the viscera 

 are held in their places. 

 That portion of the perito- 

 neum, which passes between 



viscus and the wall of the 

 cavity, usually consists of two 

 laminae, and is called an 

 omentum. There are four 

 principal omenta, viz. the 

 gastro-Jiepatic, or lesser omen- 

 tum^ which reaches from the 

 lesser curvature of the sto- 

 mach to the liver ; the gastro- 

 splenic, reaching from the left 



extremity of the stomach to the spleen ; the colic-mnentum or meso- 

 colon, which holds the large intestine to the posterior wall of the 

 abdomen ; and lastly, the gastro-colic or great omentutn or caul 

 which passes between the stomach and colon ; the last is the largest, 

 and covers the intestines like an apron ; it appears to consist of four 

 layers, whereas, like the rest, it consists but of two. Owing to its 

 great size and the proximity of the colon to the stomach, it must 

 necessarily be folded or doubled, and thus presents a quadruple 

 appearance. 



Since the peritoneum is a continuous membrane, its whole surface 

 can be traced in a male subject with the point of a finger, otherwise 

 it would not be a single sac. In the female there is a deficiency at 

 the extremity of the Fallopian tube. 



Commencing at the umbilicus to trace the peritoneum, it will be 

 found to line the anterior wall of the abdomen and under surface of 

 the diaphragm, thence to cover the upper and a part of the lower 



