836 A MANUAL OF ANATOMY 



The point at which the peritoneum leaves the rectum is fully 

 3 inches above the anus. The membrane is now carried forwards 

 to the upper ends of the vesiculae seminales, and the adjacent 

 portions of the vasa deferentia, which it covers. Thereafter it 

 passes forwards over the superior surface of the bladder, which it 

 completely covers as far as the apex. Here it meets with the 

 urachus, and by this it is conducted from the bladder to the 

 posterior surface of the anterior abdominal wall. Along each lateral 

 border of the bladder the peritoneum is reflected over the correspond- 

 ing lateral wall of the pelvis. In passing from the rectum to the upper 

 part of the base of the bladder, the peritoneum forms the recto- 

 vesical pouch. The bottom of this pouch is, as a rule, fully i inch 

 distant from the base of the prostate gland, thus leaving the part of 

 the base of the bladder, called the external trigone, quite free from 

 peritoneum. The peritoneum, as it passes to and from the bladder, 

 forms certain folds, which constitute the false ligaments of the viscus. 

 These are five in number, as follows : iiejo posterior, which represent 

 the laterally-disposed lips of the mouth of the recto-vesical pouch ; 

 two lateral, right and left, which represent the reflection of peri- 

 toneum from each lateral border of the bladder to the correspond- 

 ing lateral wall of the pelvis ; and superior, which is the reflection 

 of the peritoneum from the apex of the bladder to the posterior 

 surface of the anterior abdominal wall along the urachus. The 

 parts of the bladder which are left uncovered by peritoneum are 

 (i) the inferior surface, and (2) the external trigone. 



The pelvic peritoneum on either side of the bladder and rectum presents 

 three fossae when these viscera are empty, which are named, from before 

 backwards, paravesical, paravesicular, and pararectal. 



Retro-pubic Pad of Fat. — ^This is a collection of areolar and 

 adipose tissues which lies between the posterior aspect of the 

 bodies of the pubic bones, the bladder, and the pubo-prostatic 

 ligaments. 



Pelvic Fascia. — ^This fascia clothes the inner wall of the pelvis, 

 and furnishes inward expansions, which have an intricate con- 

 nection with, and serve to support, the contained viscera. It is 

 divisible into two portions — parietal and visceral. 



Parietal Portion. — Over the posterior wall of the pelvic cavity 

 the parietal portion of the pelvic fascia, which is here very thin, 

 covers the intrapelvic portion of each pyriformis muscle and the 

 corresponding sacral plexus, this portion being known as the 

 fascia of the pyriformis. Over the lateral wall the fascia attains 

 considerable strength, and is attached superiorly to the back part 

 of the iliac portion of the ilio-pectineal line for a short distance, 

 where it becomes continuous with the iliac fascia. In front of this 

 the fascia falls short of the ilio-pectineal line, and is fixed to the 

 lateral wall of the pelvis a little below the line, its attachment 

 being oblique, and accurately following the upper border of the 

 obturator internus muscle. When it arrives at the upper part of 



