FASCIA. 



1205 



If the superficial layer of the deep perineal fascia is detached on either side, 

 the deep perineal interspace will be exposed and the following parts will be seen 

 between it and the deep layer of the fascia : the subpubic ligament in front, close 

 to the symphysis pubis ; the dorsal vein of the penis ; the membranous portion of 

 the urethra and the Compressor urethrae muscle; Cowper's glands and their 

 ducts : the dorsal artery and the dorsal nerve of the penis ; the artery and nerve of 

 the bulb and a plexus of veins. 



The superior or deep layer of the deep perineal fascia is derived from the obturator 

 fascia or is continuous with it along the pubic arch. Behind, it joins with the 

 superficial layer of the deep perineal fascia and is continuous with the anal fascia. 

 Above it is the recto-vesical fascia, separated from it on each side by the anterior 

 fibres of the Levator ani. but in the median line these two layers of fascia are 

 continuous and form a median septum, in consequence of the recto-vesical fascia 

 dipping down to join the deep layer of the deep perineal fascia. Thus on each 



Anterior layer of 



deep perineal fascia removed, 



showing 



^COMPRESSOR URETHRA. 



'nternal pudic artery. 

 Artery of the bulb. 

 Cowper's gland. 



FIG. 769. Deep perineal fascia. On the left side the anterior layer has been removed. 



side of the middle line, beneath this fascia, is a little interspace in which is 

 contained the anterior fibres of the Levator ani (Levator prostatse). It is bounded, 

 below, by the deep layer of the deep perineal fascia ; above, by the recto-vesical 

 fascia, and is separated internally from the space on the other side by the median 

 septum. The deep layer of the deep perineal fascia is pierced by the urethra, and 

 is continued backward around the posterior part of the membranous portion of 

 the urethra and the outer surface of the prostate gland. 



The Compressor urethrae has already been described (page 464). In addition to 

 this muscle and immediately beneath it cirriOar muscular fibres surround the mem- 

 branous portion of the urethra from the bulb in front to the prostate behind, and are 

 continuous with the muscular fibres of the bladder. These fibres are involuntary. 



Cowper's glands are situated immediately below the membranous portion of 

 the urethra, close behind the bulb, and below the artery of the bulb. 



The dorsal artery and dorsal nerve of the penis are placed along the inner mar- 

 gin of the pubic arch (pages 623 and 861). 



The artery of the bulb passes transversely inward, from the internal pudic 

 along the base of the triangular ligament, between its two layers of fascia, 



