230 VISCERAL ANATOMY. 



THE PERINEUM. 



What is the Perineum ? It is a triangular space containing the structures 

 which close the pelvic outlet anterior to a line drawn between the tuberosities 

 of the ischia. Posteriorly to this line the corresponding space is named the 

 Ischio-rectal Fossa. The Perineum is bounded laterally by the rami of the 

 pubes and ischia, anteriorly by the symphysis pubis, and posteriorly by the line 

 above mentioned, which averages about 2} inches in length. 



[For the Muscles of the Perineum, see ante, p. 83.] 



THE MALE PERINEUM. 

 What Fasciae are met with in the Perineum ? The 



Superficial Layer of the Superficial Fascia, is thick, loaded with fat, and 

 continuous with the subcutaneous fascia of the thighs. 



Deep Layer of the Superficial Fascia, is thin but strong, continuous in front 

 with the dartos of the scrotum, (?), attached on each side to the rami of the 

 pubes and ischium ; posteriorly it joins the deep perineal fascia under the 

 transversus perinei muscle. It sends inwards a vertical septum which is 

 incomplete in front. [This fascia is called by Professor Pancoast the 

 "anterior leaflet of the triangular ligament."] 



Anterior Layer of the Deep Perineal Fascia, is triangular in shape, and 

 extends from the pubic arch and the sub-pubic ligament, laterally to the 

 rami of the pubes and ischia, and posteriorly to the central tendinous portion 

 of the perineum, where it becomes blended with the deep layer of the 

 superficial fascia. It embraces the anterior part of the membranous portion 

 of the urethra. [Called by Professor Pancoast, the " middle leaflet of the 

 triangular ligament."] 



Posterior Layer of the Deep Perineal Fascia, has the same attachments as 

 the anterior layer above described, but in its course it embraces the posterior 

 part of the membranous portion of the urethra, and is in connection with 

 the apex of the prostate gland. [Called by Prof. Pancoast, the " posterior 

 leaflet of the triangular ligament."] 



Obturator Fascia, is the part of the pelvic fascia which covers the obturator 

 internus muscle, and is continued on to the levator ani muscle as the Ischio- 

 rectal or Anal fascia. 



Recto-vesical Fascia, is the portion of the pelvic fascia which invests the 

 internal surface of the levator ani muscle, and the prostate gland, bladder, 

 rectum, and vesiculse seminales. 



What is Buck's Fascia ? It is a continuation of the Deep Layer of 

 the Superficial Fascia of the Perineum, extending forwards upon the penis, 

 and investing that organ completely as far as the glans. It is continuous above 



