THE MALE PERINEUM. 207 



tissues on the stretch. These ulcers are generally situ- 

 ated about a quarter of an inch or so from the verge, 

 just within the sphincter, and generally either in front 

 of, or at the side of the coccyx. The treatment consists 

 in dividing the fibres with a view to relieve the tension. 

 In operating on the female, care must be taken in mak- 

 ing the incision, if on the anterior wall of the bowel, on 

 account of the proximity of the vagina. If the verge 

 of the anus be carefully examined it will be seen to con- 

 tain a large number of follicles, suppuration in which is 

 often mistaken for fistula a disease which is frequently 

 difficult to diagnose correctly without a good view of the 

 interior of the gut, of which an inch or an inch and a 

 half must be exposed for the purpose ; and it is a fact 

 of great surgical importance that the internal opening of 

 a fistula is always within this distance of the orifice. 



The external opening of the rectum is occasionally 

 wanting (atresia ani). 



The lower, or perinea! portion of the rectum, is not 

 much more than an inch in length; it curves back below 

 the prostate, and is uncovered by peritoneum. Just 

 above the anus the rectum is considerably dilated, a con- 

 dition increased by age and constipation. The folds of 

 mucous membrane, in the empty state of the rectum, so 

 overlap, that considerable difficulty may be experienced 

 in passing the finger or a bougie through them ; one 

 fold in particular often obstructs the finger, at about an 

 inch and a half above the aperture. The mucous mem- 

 brane of the lower end of the bowel is very loose, and 

 readily admits of the burrowing of matter. It must be 

 borne in mind that the curve of the bowel above men- 

 tioned necessitates caution in the introduction of an 

 enema-tube or other instrument, which should be di- 



