115 4 PHYSIOLOGY 



The nerve-supply of the bladder (Fig. 539) is derived from two main 

 sources, namely, from the upper four lumbar nerves through the sympa- 

 thetic system, and from the second and third sacral nerves by means of 



Ant. long m. 

 Circular muse. 



Pubo-vesical m. 



Symphysis 



Ant. circular m 

 Ant. long. m. 



Os pubis _ 



Sphincter urogenitalis 



Circular 

 Longitudinal 



Os pubis 



Circular coat 

 Longitudinal coat 



Sphincter trigoni 



Prostate 



Circular coat 

 Longitudinal coat 



SpJiincter trigoni 



Circular coat 

 Longitudinal coat 



Sphincter trigoni 

 Longitudinal muscle 



Fibres running to urethro- 

 vaginal septum 



FIG. 538. Sagittal sections through neck of bladder. 



(METZNER after KALISCHEB.) 



A, in middle line (male) ; B, slightly to left of middle line (male) ; 

 c, ditto (female). 



the pelvic visceral nerves or nervi erigentes. The upper lumbar nerves 

 send white rami communicantes to the lateral chain of the sympathetic, 

 and thence to the collateral ganglia, which are grouped round the inferior 

 mesenteric artery to form the inferior mesenteric ganglion. Most of the 

 fibres end in this collection of ganglion-cells, and a new relay of axons passes 

 by two main trunks, the hypogastric nerves, into the pelvis on each side of 



