FEMALE PERINEUM 187 



division into right and left parts by the urogenital cleft. In 

 the male the pouch is less completely divided than in the 

 female; the boundaries of its anterior part are enlarged to 

 form the scrotum in which the male genital glands (the 

 testes) are lodged, and it is of special interest in relation with 

 the extravasation of urine from a ruptured urethra. In the 

 female each half of the pouch lies in the corresponding 

 labium majus. Extravasation of urine into it does not occur, 

 but it is of interest in association with the fact that occasion- 

 ally the female genital gland (the ovary) descends into it 

 instead of remaining in the pelvis. The descent of the 

 ovary into the superficial pouch of the urogenital triangle is 

 abnormal, but its occurrence should be remembered in order 

 that mistakes of diagnosis may be avoided. 



ANAL TRIANGLE. 



Nothing need be added to what has already been written 

 regarding this portion of the perineal space in the male. In 

 both sexes the steps of the dissection and the parts found are 

 precisely the same (vide p. 155). 



UROGENITAL TRIANGLE. 



Superficial Perineal Vessels and Nerves. Under this 

 heading are included : 



, , . J" The superficial perineal artery. 

 r ' \ The transverse perineal artery. 



[ The posterior labial nerves. 



Nerves, -j The long perineal branch of the posterior cutaneous nerve of 

 ( the thigh. 



The vessels and nerves mentioned lie, as in the male, in 

 the superficial pouch of the urogenital triangle, but they are 

 smaller than the corresponding structures in the male and 

 are distributed to the labia majora instead of to the 

 scrotum. 



Dissection. The superficial or posterior labial branches of 

 the perineal nerve have already been secured in the antero- 

 lateral angle of the ischio-rectal fossa (see p. 158). Now follow 

 them forwards into the superficial pouch of the urogenital area. 

 They are accompanied by the superficial branch of the perineal 

 artery which must be cleaned at the same time. As the posterior 

 labial nerves are traced forwards they will be found to be joined, 



