276 ABDOMEN 



surface of the bladder, hangs down into the pelvis close to 

 its left side. The rectum commences at the termination of 

 the pelvic colon and runs downwards and forwards to end in 

 the anal canal. Only its upper part can be seen at present, 

 the lower part being concealed by the bladder, and in the 

 female by the vagina (see Figs. 85, 224). 



It is extremely important that the surgeon, who is operat- 

 ing in the abdomen, shall be able to tell at once whether he 

 is handling a coil of small or of large intestine. The dis- 

 sector should note that the size of the coil cannot be 

 depended upon to decide the question, for the size depends 

 to a large extent on the state of contraction or distension of 

 the wall of the gut. Position is a better guide, but it also is 

 not entirely reliable, for portions of the large intestine are 

 very liable to be displaced from their usual positions. There 

 are, however, certain external characteristics of the two main 

 parts of the intestine which can always be relied upon to 

 furnish the necessary evidence, (i) The walls of the large 

 intestine are sacculated; (2) The longitudinal muscle fibres 

 of the wall of the large intestine form three definite bands, 

 two of which can usually be distinguished through the 

 peritoneum, one along the free border of the gut, that is the 

 border opposite the mesenteric attachment, or furthest away 

 from the posterior wall of the abdomen, and another which 

 lies along the medial border, in the cases of the ascending, 

 descending, iliac, and pelvic portions of the colon, and along 

 the inferior border of the transverse colon ; (3) The third 

 and, at the same time, the most easily recognisable and 

 most distinctive feature of the large intestine is the presence 

 of little fat -laden pouches of peritoneum called appendices 

 epiploicce, which are attached to the free border of the gut. 

 None of the three features mentioned in connection with the 

 large intestine are present in the case of the small intestine ; 

 on the contrary, its walls are not sacculated ; it possesses no 

 specialised longitudinal muscular bands, and it has no 

 appendices epiploicae attached to its walls. 



If the subject is a female the uterus will be found occupy- 

 ing the central part of the pelvis. It lies between the rectum 

 behind, and the bladder in front, and is connected on each 

 side to the side wall of the pelvis by a fold of peritoneum 

 called the broad ligament (see Figs. 224, 225, 228). 



The dissector should notice that the caecum presents the 



