402 A MANUAL OF ANA TO MY. 



lar fibres. They are also called the puboprostatic liga- 

 ments. 



In the female the rectovesical fascia encloses the vagina 

 and forms a sheath for it similar to the prostate in the male. 



The Anal (Ischiorectal) Fascia. Diags. 27, 28. Fig. 82. 



This is a thin layer which covers the lower surface of the 

 levator ani muscle and coccygeus muscles. Laterally, it 

 is attached to the obturator fascia close under the origin of 

 the levator ani muscle from the " white line;" behind, it 

 blends with the obturator fascia ; in front, it becomes con- 

 tinuous with the triangular ligament ; centrally, it passes 

 into the fibrous tissue about the anus. 



The prismatic-shaped cavity which is left between the 

 lower part of the obturator fascia and the anal fascia is called 

 the ischiorectal fossa. 



The Deep Layer of the Triangular Ligament. Diags. 



26, 27, 28. 



Posteriorly, this ligament becomes continuous with the 

 anal fascia (also the superficial layer of the triangular liga- 

 ment and the perineal fascia, as will appear later). Later- 

 ally, it is attached all along the inner margin of the rami of 

 the ischium and pubes ; anteriorly, to the subpubic ligament, 

 leaving here an opening for the single dorsal vein of the 

 penis. The upper surface of the deep layer of the triangular 

 ligament is continuous at the anterior margin of the levator 

 ani muscle with the rectovesical fascia, which here forms the 

 capsule for the prostate gland. The prostate gland rests 

 upon this portion of the triangular ligament as on a shelf. 



The triangular ligament (deep portion) is perforated at 

 its apex by the dorsal vein of the penis ; at its base centrally, 

 by the membranous urethra ; at its base laterally, by the 

 pudic artery, vein, and dorsal nerve of the penis. 



