782 THE URINARY TRACT. 



the urethra, the circular layer being most marked in the mem- 

 branous portion, and freely connecting with the striped muscles 

 which surround this part. In the prostatic portion the longitu- 

 dinal fibers are more developed especially, it is maintained, in the 

 region of the colliculus seminalis. The cavernous portion has a 

 limited amount of longitudinal and circular bundles of muscle- 

 fibers. The veins of the urethra, according to Henle and C. 

 Langer, produce a plexus in the submucous layer, which is very 

 large, especially in the prostatic and membranous portions, and 

 is distinctly marked, also, in the cavernous portion from the cav- 

 ernous body of the urethra proper. The latter is composed of 

 comparatively narrow venous spaces, inclosed by trabeculas of a 

 fibrous connective tissue, which hold numerous small bundles of 

 smooth muscle-fibers. At the periphery the cavernous body is 

 insheathed by a layer of very dense, fibrous connective tissue 

 the tunica albuginea which is also provided with bundles of 

 smooth muscle-fibers, being mostly circular, and connected with 

 those of the trabeculae of the cavernous body. 



