THE ABDOMINAL CAVITY 277 



The Peritoneum is a highly absorptive serous membrane, 

 which lines the abdominal and pelvic cavities (parietal layer), 

 and is more or less intimately related to the viscera contained 

 by them (visceral layer). In the male it' forms a completely 

 closed sac, but in the female it communicates with the cavities 

 of the uterus and vagina through the ostium abdominale of the 

 uterine (Fallopian) tube. Infective conditions, therefore, may 

 ascend to the peritoneal sac through the vagina, uterus, and 

 tubes, as, for example, in acute gonorrhceal peritonitis. 



The deep surface of the anterior abdominal wall is completely 

 lined by peritoneum. Below the umbilicus it forms an 

 uninterrupted sheet so that when the cavity has been opened, 

 the hand may be introduced and passed across to the opposite 

 s : de without meeting any normal obstruction. Above the 

 umbilicus, a fold of peritoneum, consisting of two layers the 

 falciform ligament passes backwards to the liver and forms 

 an imperfect partition. Its lower border, where the two 

 constituent layers become continuous, is free and contains the 

 ligamentum teres and the associated para-umbilical veins (p. 243). 

 Although its anterior attachment is in the middle line, the 

 falciform ligament passes backwards and slightly to the right. 

 On this account, when supra-umbilical median incisions are 

 enlarged in a downward direction, they should be carried round 

 the left s'de of the umbilicus, so as to obviate the necessity for 

 cutting through the ligamentum teres and the associated veins. 



The peritoneum lining the anterior abdominal wall sweeps 

 upwards on to the inferior surface of the diaphragm, and is 

 then reflected on to the liver (Fig. 85) and stomach. Between 

 the hepatic and gastric reflections, the peritoneum on the under 

 surface of the diaphragm becomes continuous with the anterior 

 layer of the lesser omentum. 



In Fig. 85 the peritoneum is shown passing from the 

 diaphragm to the liver in two layers, which cover its anterior 

 and posterior surfaces and meet on the inferior surface at the 

 porta hepatis (transverse fissure). They then descend to the 

 lesser curvature of the stomach as a broad sheet which is termed 

 the lesser omentum. After enclosing the stomach and con- 

 stituting its serous coat they again meet one another, and 

 descend for a variable distance towards the pelvis. Inferiorly 

 they are folded sharply upwards and ascend to the transverse 

 colon. This large peritoneal sheet, which connects the transverse 

 colon to the stomach, is termed the greater omentum. 



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