Chap, xvni.] THE RECTUM. 375 



spine, the sacrum, etc. " In some subjects even a 

 small hand cannot be passed beyond the reflection of 

 the peritoneum over the second part of the gut. In 

 such instances the peritoneum offers a resistance like a 

 tight garter, and prevents the farther advance of the 

 hand without great risk of laceration of the parts " 

 (Walsham). 



Mr. Davy has invented a wooden " lever," by 

 which the common iliac arteries may be compressed 

 against the pelvic brim through the rectum. The 

 lever has proved of particular value in arresting 

 haemorrhage during amputation through the hip 

 joint. 



The attachments of the rectum by means of the 

 pelvic fascia are not very firm ; since, in some severe 

 and rare cases of prolapse, all the walls of the gut 

 may be protruded at the anus. In excision of the 

 rectum, also, advantage is taken of this mobility. 

 In that operation the lower two inches or more 

 of the bowel may be removed, and the remaining part 

 of the tube drawn down so that its mucous membrane 

 can be stitched to the edges of the wound. 



The mucous membrane is thick, vascular, and but 

 loosely attached to the muscular coat beneath. This 

 laxity, which is more marked in children, favours pro- 

 lapse, an affection in which the mucous membrane of 

 the lower part of the rectum is protruded at the anus. 

 The mucous membrane presents three prominent semi- 

 lunar folds, about half an inch in depth, which are 

 placed more or less transversely to the long axis of the 

 bowel. The first projects backwards from the fore 

 part of the rectum opposite the prostate, the second 

 projects inwards from the left side of the tube opposite 

 the middle of the sacrum, the third is near the com- 

 mencement of the bowel on the right side. These 

 folds, especially when the gut is empty, may offer con- 

 siderable resistance to the introduction of a bougie or 



