606 FEMALE PELVIS. 



is enveloped. Sometimes it becomes dilated towards its extremity, but 

 more frequently retains the same diameter throughout. 



The Fas deferens may be traced upwards in the course of the seminal 

 fluid, from the globus minor of the epididymis along the posterior part 

 of the spermatic cord, and along the spermatic canal to the internal ab- 

 dominal ring. From the ring it is reflected inwards to the side of the 

 fundus of the bladder, and descends along its posterior surface, crossing 

 the direction of the ureter, to the inner border of the vesicula seminalis. 

 In this situation it becomes somewhat larger in size and convoluted, 

 and terminates at the base of the prostate gland, by uniting with the 

 duct of the vesicula seminalis and constituting the ejaculatory duct. 

 The ejaculatory duct, which is thus formed by the junction of the duct 

 of the vesicula seminalis with the vas deferens, passes forwards to the 

 anterior extremity of the veru montanum, where it terminates by open- 

 ing into the prostatic urethra. 



FEMALE PELVIS. 



The peculiarities in the form of the female pelvis have already been 

 examined with the anatomy of the bones (p. 94). Its lining 

 boundaries are the same with those of the male. The contents are, 

 the bladder, vagina, uterus with its appendages, and the rectum. 

 Some portion of the small intestines also occupies the upper part of 

 its cavity. 



The Bladder is in relation with the os pubis in front, with the uterus 

 behind, from which it is usually separated by a convolution of small 

 intestine, and with the neck of the uterus and vagina beneath. The 

 form of the female bladder corresponds with that of the pelvis, being 

 broad from side to side, and often bulging more on one side than on 

 the other. This is particularly evident after frequent parturition. The 

 coats of the bladder are the same as those of the male. 



The Urethra is about an inch and a half in length, and is lodged in 

 the upper wall of the vagina in its course downwards and forwards, 

 beneath the arch of the os pubis, to the meatus urinarius. It is lined by 

 mucous membrane, which is disposed in longitudinal folds, and is con- 

 tinuous internally with that of the bladder, and externally with the 

 vulva ; the mucous membrane is surrounded by a proper coat of elastic 

 tissue, to which the muscular fibres of the detrusor urinae are attached. 

 It is to the elastic tissue that is due the remarkable dilatability of the 

 female urethra, and its speedy return to its original diameter. The 

 meatus is encircled by a ring of fibrous tissue, which prevents it from 

 distending with the same facility as the rest of the canal ; hence it is 

 sometimes advantageous in performing this operation to divide the 

 margin of the meatus slightly with the knife. 



VAGINA. The Vagina is a membranous canal, leading from the 

 vulva to the uterus, and corresponding in direction with the axis of 

 the outlet of the pelvis. It is constricted at its commencement, but 



