FEMALE PERINEUM 367 



and the posterior border of the orifice of the vagina, is a 

 depression, the fossa navicularis. 



The frenulum pudendi may be absent, and if present it is 

 usually ruptured during the first labour. 



It may be well for the student to bear in mind that the term " perineum " 

 is used by obstetric surgeons in a very restricted sense. It is applied by 

 them to the small region between the anus and the frenulum labiorum 

 pudendi. 



Clitoris. The clitoris is the homologue of the penis, and, 

 notwithstanding its diminutive proportions, it presents a 

 close resemblance to the male organ both in appearance and 

 structure. It is a minute elongated projection placed below 

 the anterior commissure, and surmounted by a sensitive 

 rounded tubercle called the g/ans, but it is not traversed by 

 the urethra. The manner in which its prepuce and frenum 

 are formed has already been described. To obtain a proper 

 view of the clitoris the student must lay hold of the glans 

 with the forceps and draw it out from the prepuce. 



Vestibule. The dissector should next take note of a 

 smooth triangular interval which exists between the clitoris 

 and the entrance to the vagina. The term vestibule is given 

 to this area. It is bounded laterally by the labia minora, and 

 towards its lower part or base is seen the orifice of the 

 urethra. 



The triangular outline of the vestibule is only seen when 

 the labia are forcibly drawn apart from each other. In the 

 natural condition of parts the labia are in close apposition, and 

 the vestibule is then a deep recess which represents the bottom 

 of the pudendal cleft, between the clitoris and the vagina. 



Urethra! Orifice. This lies close to the opening of the 

 vagina, about one inch below the clitoris. It usually presents 

 the appearance of a vertical slit, and the mucous membrane 

 around it is prominent, pouting, and slightly puckered, so that 

 when the tip of the finger is passed over the vestibular area 

 the opening can readily be distinguished by touch. 



Vaginal Orifice. The vaginal opening in the virgin is 

 partially closed by the hymen formed by two semilunar folds 

 of mucous membrane attached to the sides of the entrance 

 to the vagina, and united together anteriorly and posteriorly. 

 The form of the hymen, however, is very variable. Some- 

 times it is present in the shape of a septum attached around 

 the entire circumference of the vaginal entrance, but 



