THE FEMALE UKETHKA. 



1285 



, 



Structure. The wall of the female urethra is thick and contains much fibrous 

 tissue, which passes without any sharp line of demarkation into the surrounding mass of 

 connective tissue. The tunica muscularis or muscular coat of the urethra is continuous 

 above with that of the bladder, and is composed of layers of circularly and longitudi- 

 nally disposed smooth muscle fibres arranged to form outer and inner strata. Within 

 the muscular coat the wall of the urethra is very vascular, and the canal itself is lined 

 by a pale mucous membrane which is thrown into longitudinally directed folds, one of 

 which is the crista urethralis mentioned above. The epithelium of the canal, in its upper 

 part, is of the transitional variety, like that of the bladder ; in its lower part it becomes 

 scaly. Numerous minute glands, the glandulse urethrales, and pit-like depressions 



Ureter 



Nerve cords 

 from hypo- 

 gastric plexus 



Recto-uterine 



fold 



Utero-vesical 



pouch 



Recto-uterine 



pouch 



Orificium exter- 

 num uteri 



Vagina 



abium minus 

 abium majus 



FIG. 1002.- 



-MEDIAN SECTION THROUGH THE FEMALE PELVIS. Drawn for the most part from a model 

 of a dissection by Professor Edward H. Taylor. 



[lacunae urethrales) open into the urethral canal. One group of these glands on each 

 dde possesses a minute common duct known as the ductus paraurethralis, which opens 

 ; nto the rima pudendi or urino-genital cleft by the side of the urethral orifice. It is 

 aelieved that these latter glands represent the prostatic glands of the male subject. 

 The vascular layer which lies between the muscular coat and the mucous membrane 

 contains elastic fibres, and in appearance resembles erectile tissue. Striped muscle fibres 

 ire present on the outer aspect of the muscular coat of the urethra. In the upper part 

 ')f the canal these fibres form a complete ring-like sphincter, but in the middle and lower 

 )arts the striped muscle fibres though present in front are absent on the posterior wall of 

 -he urethra, as at this level they pass backwards on the outer aspect of the vagina, and 

 'snclose this latter passage together with the urethra in a single loop of muscle tissue. 

 The lower fibres, therefore, form a urino-genital sphincter. 



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