586 ABDOMEN | 



upper end, and pinch in its walls. The membranous 

 part of the urethra and the bulb of the urethra are in 

 front of the canal, but, on account of the backward inclination 

 of the gut, they are separated from it by a mass of fibro- 

 elastic tissue corresponding to the perineal body of the 

 female. Behind the anal canal is the ano-coccygeal body 

 (Symington). 



Vesica Urinaria (Bladder). This is a hollow viscus, with 

 strong muscular walls, which acts as a temporary reservoir for 

 the urine before it is emitted from the body by the process 

 of micturition. Its form, and, in a great measure, its position 

 and relations, are influenced by the amount of fluid it contains 

 and by the age of the subject. 



Ureter 



Superior urface 



Seminal,, 

 vesicle !,._ .._ 



L rachus 



s lnfero-lateral surface 



\ *uyr 



Prostate ^- 



-Membranous urethra 



FIG. 232. Bladder hardened in situ viewed from the right side. 

 It contained a very small quantity of fluid. (A. F. Dixon. ) 



The different forms which the bladder assumes, under con- 

 stantly changing conditions, render its description a matter 

 of serious difficulty. As a rule it is found in the dissecting 

 room with contracted walls and empty. For this reason, 

 and also because our information regarding the empty bladder 

 is more exact, the dissector should study, in the first place, 

 the form it presents when in this condition, and afterwards 

 consider the changes it undergoes as it becomes filled with 

 urine. The following description is based upon the account 

 given by Professor Dixon. 



The empty bladder lies completely within the cavity of the 

 pelvis. It has the form of a triangular pyramid possessing 

 -an apex, a base or fundus and three surfaces, viz. a superior 

 and two infero-lateral surfaces. 



1\& fundus looks backwards towards the rectum, from which 



