VISCERAL ANATOMY. 151 



skin externally, and mucous membrane internally. The different 

 structures composing it are the clitoris, urethra and hymen. 

 The Clitoris. 



This is a body two or three inches long; lies at the inferior 

 commissure; is composed of erectile tissue, two crura, a prepuce 

 and glans. 

 The Female Urethra. 



Is very short, and opens by its meatus about three or four 

 inches from the vulva on its inferior wall. It is guarded by a 

 mucous valve which directs the urine backward. Its calibre is 

 greater than in the male. Its coats are an internal mucous and 

 external muscular, of circular fibres. 

 The Hymen. 



Rare. A thin, fibrous structure, shutting off the vaginal from 

 the vulvar cavities. It is perforated by several openings. 

 Structure of Vulva. 



Mucous membrane, with many mucous and sebaceous glands. 



Bulb of Vulva. Consists of two lateral lobes of erectile tissue, 

 communicating with the vessels of the clitoris, lying on either side 

 of the vulva. 

 Muscles. 



Constrictor vulvce. 



Attachments. Above to sacrum and sphincter, and below to 

 clitoris; laterally to muscles of thigh. 



Action. Constricts vulvar orifice. 



Constrictor vagina. 



Attachments. To sides of rectum and vagina at junction with 

 vulva. 



Action. Constricts vagina. 



THE VAGINA. 



The vagina is a long, membranous tube, extending from the 

 vulva to the uterus, and serves the purposes of coition and passage 

 of the foetus. 



Relations. 



Above, rectum; below, bladder; laterally, ureters and con- 

 nective-tissue. 



Structure. 



Inner or Mucous Coat. Pale; a basement membrane, covered 



