DISSECTING MANUAL. 



When distended the angles and borders become rounded and 

 obliterated, the lateral borders forming the "lateral surfaces." 

 The outline becomes oval or circular, and the highest part, a 

 point behind the apex, rises into the abdominal cavity. In 

 normal distention it will hold about a pint. [1 147] 



Relations. The base rests, in the male, on the rectum below 

 the recto-vesical pouch, separated by the seminal vesicles, 

 vasa deferentia, and recto-vesical layer of pelvic fascia; in the 

 female it lies on the vagina and lower part of the uterus below 

 the utero-vesical pouch. When empty, the vas deferens lies 

 above and parallel to the lateral border, only coming in relation 

 with the base after crossing the ureter; the obliterated hypo- 

 gastric artery lies often an inch above the lateral border. 

 When distended, both the vas and (often) the obliterated hy- 

 pogastric cross its side wall; the apex lies an inch and a half 

 or more above the symphysis. [1147] 



Interior. The mucous membrane is generally loosely con- 

 nected and forms folds in the empty bladder. It is firmly con- 

 nected, and does not form folds, on a triangular smooth area 

 (trigonum vesicce) which lies over the base and is bounded by 

 lines connecting the internal orifices of the urethra and ure- 

 ters. The middle lobe of the prostate causes a bulging (uvula 

 vesicce) just behind the urethral orifice, often well marked in old 

 people. A smooth curved ridge, caused by a transverse bundle 

 of muscle fibres, stretches between the ureteral orifices; its 

 lateral portions (plicae uretericce) are produced by the ureters. 

 Minute folds radiate from the urethral orifice. The ureteral 

 orifices are elliptical, an inch apart when the bladder is empty, 

 half an inch more at least when full. [1 151] 



Peritoneal Relations. Peritoneum covers the superior sur- 

 face only. From each lateral border it passes (lateral false 

 ligaments) to the pelvic wall at the white line, lining a groove 

 (paravesical fossa) which is present on each side when the 

 bladder is empty. Anteriorly it passes (anterior false liga- 

 ment) over the urachus to the anterior abdominal wall, at the 



[234] 



