238 Anatomy Applied to Medicine and Surgery. 



In the descending colon the posterior longitudinal 

 band is not of as much assistance in identifying the bowel 

 as it is in the ascending portion, since, in the former the 

 longitudinal bands spread out more or less as the sigmoid 

 and rectum are approached. In iliac colotomy, or ccelio- 

 colotomy, the incision may be made, one-half above and 

 one-half below a line drawn from the left anterior supe- 

 rior spinous process to the umbilicus, and the same struc- 

 tures divided as in the operation for exposing the ap- 

 pendix. 



