PELVIS 



589 



As the bladder fills its superior wall is raised from the 

 fundus and infero-lateral walls. All its surfaces are increased 

 in area, and the borders, which in the empty bladder inter- 

 vene between them, become rounded off and finally obliterated. 

 The organ thus becomes oval in form, and the walls, which 

 are thick and firm in the contracted state, become com- 



Rectu* 

 abdominis 



Pyramidalis 



i- Peritoneum 



P>ulbo-cavernosus 



FIG. 235. Medial section through the Pelvis of an Adult Male. The 

 bladder is nearly empty, and the urethra is divided along its whole 

 length. 



R. Rectum. 



S. Symphysis. 



B. Bladder. 



paratively thin. The apex appears above the symphysis 

 pubis, and, as distension goes on, the organ rises higher and 

 higher into the hypogastric region until a considerable extent 

 of its wall becomes applied to the abdominal wall above the 

 pubis. The infero-lateral surfaces of the distending bladder 

 encroach on the paravesical fossae, and finally obliterate them, 

 thus coming into contact with a greater extent of the lateral 

 walls of the pelvis. 



When the bladder is excessively distended it assumes a 



