THE VAGINA. 



2017 



Douglas. Below the latter, as far as the levator ani muscles, the vagina and bowel 

 are connected by the dense recto-vaginal septum, strengthened by the intervening 

 prolongation of the pelvic fascia. Further down, where the rectum bends backward, 

 the partition broadens into a wedge-shaped mass, the perineal body, which on 

 sagittal section appears as a triangle with the base below in the perineum (Fig. 1700). 

 At the sides the vagina is embraced by, although unattached to, the median (pubo- 

 rectal) portion of the levator ani muscles, which, in conjunction with the pelvic fascia, 

 afford efficient support. Below the pelvic floor, the vagina gains additional fixation 

 in passing through the triangular ligament with which it is intimately attached. In 

 relation with the lower end of the vagina lie the bulbus vestibuli and Bartholin's 

 glands. The triangular interval, on each side, between the levator ani and the pelvic 

 fascia and the lateral surface of the vagina, is occupied by the veins of the vesico- 



FIG. 1 704. 



Pubo-vesical ligamen 



Pelvic fascia covering 

 levator ani 



Obturator membrane.^ 



Visceral exten- 

 sion of pelvic, 

 fascia 



Obturator fascia. 

 Fat removed ex 

 posing pelvic floor 

 Visceral reflec- 

 tion of pelvic 

 fascia 



Obturator 

 internus 

 Levator ani 



Ischium, cu' 



Anal fascia 



Symphysis pubis 

 Pubic bone, cut 



Prevesical space, 

 cleaned out 



Portion of wall 

 of bladder 



Urethra 



-Vesico-vaginal 

 venous plexus 



Ischio-rectal fossa 



Anterior portion of horizontal section through pelvis, of remale, passing just below bladder ; 

 visceral reflections of pelvic fascia are seen extending to bladder, vagina, and rectum. 



vaginal plexus that above surrounds the ureter and the vaginal branches of the 

 uterine artery. 



Structure. The vaginal walls, from 2-3 mm. thick, include a mucous and a 

 muscular coat, supplemented externally by an indefinite fibrous tunic. The mucous 

 coat consists of a tunica propria, exceptionally rich in elastic fibres and veins, the 

 inner surface of which is beset with numerous conical papillae that encroach upon the 

 overlying epithelium, but do not model the free surface. The epithelium, from 

 o. 15-0.20 mm. thick, is stratified squamous in type and possesses a superficial stratum 

 of plate-like cells (.020 .030 mm. in diameter) that resemble the epidermal ele- 

 ments of the skin and are constantly undergoing maceration and abrasion. Although 

 normally moistened by a thin mucous secretion of acid reaction, the vagina is devoid 

 of true glands and probably derives its lubricating fluid for the most part from the 

 uterine glands, the alkaline secretion becoming modified. Small nodules of lymphoid 

 tissue are scattered within the mucosa, especially in the upper part of the canal. 

 The duplicature of the mucous membrane forming the hymen corresponds in structure 

 with that lining other parts of the canal. The muscular coat, which directly sup- 

 ports the mucosa without the intervention of a submucous tunic, consists of bundles 

 of involuntary muscle that are arranged, although not with precision, as an inner 

 circular and an outer longitudinal layer. The latter is best developed over the 



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