THE MALE PERINEUM. 205 



in advanced age, and closely bordering on the margin of 

 the anus ; this fact is of importance, as there is greater 

 danger of wounding the bulb in the lateral operation of 

 lithotomy in old persons. The cms penis and its muscle 

 should now be drawn outwards (or entirely removed), 

 and the rectum drawn downwards, when the anterior 

 surface of the triangular ligament will be seen as a tough 

 bluish-white structure the fibres of which are nearly all 

 transverse allowing of the structures between the two 

 layers being readily seen through it in favorable subjects; 

 its base is directed towards the rectum, it is attached in 

 the middle line to the central tendon of the perineum, 

 and laterally to the rami of the ischium and pubes, hav- 

 ing a free margin on either side of the central tendon, 

 which is continuous with the deep layer of superficial 

 fascia ; its apex is directed upwards, and is connected 

 with the periosteum in front of the symphysis pubis. Tt is 

 perforated at about an inch below the symphysis by the 

 urethra, with which it is intimately connected, and which 

 here changes its direction, and between the urethra and 

 the symphysis lie the vessels of the penis, the dorsal 

 vein or veins in the centre, on either side of it the dorsal 

 arteries, and most externally are the dorsal nerves. 



The bulb may now be separated from the triangular 

 ligament (if both sides of the perineum be available), 

 turned upwards, and the triangular ligament itself care- 

 fully detached from the bone. A considerable plexus 

 of veins is usually first met with, and care must be taken 

 not to divide it, as the blood would obscure the view of 

 the parts between the layers of the triangular ligament, 

 which consist of the following structures, a plane of 

 muscular fibres, variously described by different authors, 

 as the levator and compressor urethras, surrounding the 



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