838 



A MANUAL OF ANATOMY 



levator ani to blend with that portion of the visceral pelvic fascia 

 which ensheathes the prostate gland. 



In the direction of a line passing from the inner aspect of the 

 ischial spine to the back of the body of the os pubis, near its lower 

 end and close to the symphysis, the lateral pelvic fascia is strength- 

 ened by fibres which impart to it a white colour. This part is called 

 the white line, and it serves to divide the fascia into two portions, 

 upper or pelvic proper, and lower or perineal. The pelvic portion 

 looks into the pelvic cavity, and covers the upper part of the 

 obturator internus, whilst it is itself covered by the peritoneum. 

 The perineal portion covers the lower part of the obturator internus, 

 and lies on the outer wall of the ischio-rectal fossa, where it con- 

 structs Alcock's canal. The under aspect of the white line affords 

 extensive origin to the levator ani muscle. 



Parietal Pelvic Fascia 



Levator Ani ... 



Anal Fascia ^^ij^'Wr.?: 

 Obturator Internus- 

 Parietal Pelvic Fascia-''' 1 ^i" 



Alcock's Canal 



Visceral Pelvic Fascia 



^— ..Vesicula Seminalis 



Vas Deferens 



Fig. 364. — Diagram of the Pelvic Fascia from Behind. 



Visceral Portion of the Pelvic Fascia. — ^The visceral portion is 

 destined to support the lower part of the bladder, vesiculae 

 seminales, terminal portions of the vasa deferentia, prostate gland, 

 and rectum. It is a laminar offshoot of the parietal portion, from 

 which it springs along the white line. Though, however, this is 

 its piincipal source, it has an independent origin anteriorly on 

 either side of the middle line from the posterior aspect of the body 

 of the OS pubis near the lower part of the symphysis. In this latter 

 situation it lies a little above the attachment of the parietal por- 

 tion, the anterior fibres of the levator ani taking origin from the 

 portion of bone between the two fasciae. Though the visceral por- 

 tion forms one continuous sheet along its pelvic attachment, its 

 ultimate disposition is so intricate that it is convenient to consider 

 its arrangement under three divisions. 



I. opposite the Madder, vesicula seminalis, and rectum. In 

 this region the visceral portion of the fascia passes inwards as far 

 as the outer border of the vesicula seminalis. In doine: so it covers 



