174 ANATOMY OF THE ABDOMEN, ETC. 



membrane, reflected from its own walls. We have only 

 conceive this sac as large enough to admit of many viscera 

 protruding into it, and we have an idea of the peritoneum 

 some of the viscera it merely passes over, without invest 

 ing them on all their sides, and all of them are, in reality, 

 outside the membrane. The folds made by the peritoneum, 

 either in its reflections from the viscera which it has in- 

 vested, or in passing from one organ to another, constitute 

 means of support, and hold them in their proper places ; 

 these in certain instances are improperly, though very con- 

 veniently, called ligaments, in others omenta, and in still 

 other instances mesenteries; besides supporting the organs, 

 they contain the various vessels and nerves destined to the 

 different parts. 



The great amentum is formed by two folds of the peritoneum, which 

 descend from the larger curvature of the stomach, covering in the small 

 intestines, then, doubling upon themselves, they return to be attached 

 to the transverse colon ; it therefore consists of four thicknesses ; they 

 are not, however, easily separable. The great omentum contains a 

 variable amount of fat, is sometimes perforated with holes, aud is 

 not unfrequently gathered up in a mass near the stomach. 



The lesser omentum is the fold extending between the smaller curva- 

 ture of the stomach and the liver; it contains the portal vein, hepatic 

 artery and ducts ; its left side is continuous with the oesophagus, but 

 its right forms a free margin, beneath which the finger may be passed 

 into the cavity of the peritoneum behind the stomach ; this passage 

 is called the foramen of Winslow. 



The gastro-splenic omentum passes from the outer border of the sto- 

 mach to the spleen, and contains the splenic vessels. 



The mesentery proper is that fold of the peritoneum which holds 

 down the small intestine, and which is attached posteriorly to the 

 front of the spine ; it is about four inches wide, and between its two 

 layers, besides a considerable amount of fat, are the arteries, veins, 

 and nerves of the small intestine, also the lymphatic vessels and 

 glands, called the mesenteric glands. 



The transverse meso-colon is the mesentery of the transverse colon, 

 and its medium of connection with the posterior wall of the abdomen. 



The meso-rectum and meso-ccecum are similar folds connected with the 

 rectum and caecum. The meso-csecum is of such length as to permit 

 great mobility to the caecum, though it is usually described as closely 

 bound to the iliac fossa. A left inguinal hernia of the caecum may 

 occur. 



The complications of the peritoneum are not easily com- 

 prehended, and it is only after a good deal of thought and 

 repeated examination that they can be fully understood. 

 In tracing the continuity of this membrane from above 

 downward, the student begins at the liver, where he will 



