Chap, xvn.} ABDOMINAL VISCERA. 323 



membrane may, on the one hand, lead to fatal peri- 

 tonitis, while, on the other, it may be extensively 

 torn from its attachments (as in ligaturing the common 

 iliac artery from the side) without any peritonitis 

 following. Or, again, a little pus escaping on the 

 inner surface of the membrane may lead to inflam- 

 mation, while the outer surface may be bathed 

 with pus for a long while (as in large perirenal 

 abscesses) without any peritonitis being produced. 

 Inflammation of the peritoneum may lead to the 

 formation of a great variety of bands and adhesions, 

 beneath which pieces of intestine may be caught and 

 strangulated. 



The peritoneum will allow of very considerable 

 stretching if only that stretching be effected gradu- 

 ally. This is frequently seen in cases of gradual dis- 

 tension of the bowel, and in the formation of the sac 

 in hernia. Abrupt stretching of the membrane 

 leads to certain rupture of it. The parietal peri- 

 toneum may be ruptured by violence without damage 

 to any of the viscera. 



The great oineiituin is, from its position, 

 very apt to be wounded. In small wounds of 

 the front of the belly it very often protrudes 

 and acts as an excellent plug to prevent the 

 escape of other and more important structures. 

 It is often found in hernia, especially in umbilical 

 hernia, where it is almost constant. Its limits 

 vary, and it has an inclination to the left side. This 

 depends upon the fact that the omentum is developed 

 from the meso-gaster, and accounts for the fact that 

 hernias containing omentum are much more common 

 on the left side. The omentum, like other parts of 

 the peritoneum, is apt to inflame, and to contract 

 adhesions to the neighbouring parts. These adhesions 

 are often of the greatest service in limiting inflam- 

 matory and hsemorrhagic extravasations, by matting 



