THE BLADDER. 79 



cious conformation has generally been attended with a conge- 

 nital obstruction of the urethra.* When the anterior parietes 

 of the abdomen are put upon the stretch, a semi-lunar fold of 

 the peritoneum, as formerly mentioned, is seen to proceed, on 

 either side of the urachus, from the lateral surface of the blad- 

 der almost to the umbilicus. These folds contain, in their 

 loose edge, the fibrous remains of the umbilical arteries of the 

 foetus, called, subsequently to uterine life, the Round Ligaments 

 of the bladder, though they have little or no influence on its 

 position. The bladder is also fixed in its situation by the pel- 

 vic aponeurosis, a membrane elsewhere described with the 

 organs of generation. 



The bladder consists of four coats: the Peritoneal, the Mus- 

 cular, the Cellular, and the Mucous. 



The Peritoneal Coat is very imperfect, and is derived from 

 the part of the peritoneum which descends from the anterior 

 parietes of the abdomen into the pelvis. It covers the upper 

 and the posterior face of the bladder, and then passes to the 

 rectum, by sinking down between these two organs, so as to 

 form the small pouch beneath the lower fundus of the bladder; 

 the apex of this pouch reaches within an inch of the base of the 

 prostate. The upper margin of this pouch next to the bladder, 

 forms a strong horizontal doubling, stretching across the pelvis, 

 when the rectum is empty, and is on a level with the posterior 

 end of the vesiculae seminales. Being connected to the subja- 

 cent muscular coat by a thin lamina of loose cellular membrane, 

 the peritoneum may be dissected off without difficulty. In con- 

 siderable distentions of the bladder, it is reflected from the up- 

 per end of the latter to the abdominal muscles in a line much 

 above the pubes; whereby a good opportunity is afforded of 

 reaching, with an instrument, the cavity of the bladder without 

 injuring the peritoneum. 



The Muscular Coat is of a thickness intermediate to that of 

 the stomach and of the oesophagus, and its fibres are pale. 

 They pass in very varied directions,-)- and are collected into 

 flattened fasciculi, leaving interstices between them, through 

 which the internal coat is occasionally caused to protrude, in 



* Sabatier, Anat. vol. iii. p. 19. 

 t Suntorini, SeptcmcL Tabul. 



