504 DISSECTION OF THE PELVIS. 



fat has been cleared from the rectum without injuring its arteries, the 

 pouch of the peritoneum, in which tow has been placed, will be brought 

 into view, with the ureter (/>) passing to the bladder across its side. 



The part of the Madder below the peritoneum is to be cleaned, and the 

 vas deferens (f), which lies on the lateral aspect of the viscus, is to be 

 followed down to the seminal sac. Take away with care the remains of 

 the sheath of the vesicula seminalis, defining at the same time the vas 

 deferens inside the latter. 



The peritoneum does not envelop the viscera in the pelvis so completely 

 as in the upper part of the abdomen. After partly surrounding the upper 

 portion of the rectum, and fixing it by a process mesa-rectum, the mem- 

 brane clothes the back of the bladder, projecting for some way between 

 this viscus and the rectum, where it forms the recto- vesical pouch : on 

 each side the serous membrane is arrested by the obliterated hypogastric 

 artery, and gives rise to a fold, the posterior ligament of the bladder. It 

 covers the posterior surface, and each lateral region of the bladder as far 

 forwards as the obliterated hypogastric ; but at that cord it is reflected to 

 the wall ot the pelvis and abdomen. All the anterior surface of the blad- 

 der is therefore uncovered by peritoneum ; and when the bladder is dis- 

 tended it rises above the pubes, so as to allow of its being punctured in 

 front without injury to the serous membrane. 



The recto-vesical pouch is wide behind, where it corresponds with the 

 interval between the iliac arteries, and is narrow in front between the 

 rectum and the bladder. Anteriorly it extends slightly into the interval 

 between the vesiculae seminales, and ends usually about one inch and a 

 half from the tip of the coccyx. The distance of the pouch from the anus 

 is commonly about four inches ; but it will vary with the state of the 

 bladder, for if this viscus is distended the peritoneum will be raised, and 

 removed farther from the end of the intestine. 



False ligaments of the bladder. Where the peritoneum is reflected 

 from the bladder to the pelvic wall, it gives rise to a wide piece of mem- 

 brane, which constitutes the false ligaments of that viscus, though without 

 any subdivision of it into pieces. These are said to be five in number 

 two posterior, two lateral, and one superior. 



The posterior ligament (one on each side) reaches from the back of the 

 pelvis to the bladder, and contains the obliterated hypogastric artery, the 

 ureter, and smaller vessels, and nerves. Between these is the hollow of 

 the recto-vesical pouch. 



The lateral ligament, also one on each side, the widest, is reflected from 

 the side of the bladder to the iliac-fossa and the wall of the pelvis. Along 

 its line of attachment to the bladder is the obliterated hypogastric artery. 



The superior ligament is prolonged from the top of the bladder to the 

 abdominal wall, along the remains of the obliterated hypogastric vessels. 



The RECTUM, or the lower part of the great intestine (fig. 174, &) ex- 

 tends from the articulation between the sacrum and the left hip bone to 

 the anus, and is kept in place by the peritoneum, the recto-vesical fascia, 

 and the levatores ani. The intestine is about eight inches long, and has 

 a winding course, for it follows the curve of the sacrum and coccyx: it is 

 divided into three parts upper, middle, and lower. 



The upper part, longer than the others, extends obliquely from the 

 BUCTO-iliac articulation to the centre of the third piece of the sacrum. Sur- 

 rounded almost entirely by the peritoneum, it lies against the sacrum, and 

 on the pyriformis muscle and sacral plexus of the left side. In contact 



