CONSTRICTOR URETHRA. 



249 



the pudie vessels with their branches to the bulb, and the dorsal 

 nerves of the penis. 



Dissection. The muscle between the layers of the ligament will Dissection, 

 be reached by cutting through with care, on the left side, the 

 exposed stratum near its attachment to the bone, and raising and 

 turning it inwards. By a little cautious dissection, and the removal 



Fi. 



94. DEEP DISSECTION OF THE PERINEUM (ILLUSTRATIONS OF 

 DISSECTIONS). 



Muscles, tt-c. : 



A. Erector penis. 



B. Ejaculator urinse, cut. 



c. Triangular ligament, inferior 

 layer. 



D. External sphincter. 



F. Bulb of corpus spongiosum. 



<T. Levator ani. 



H. Superior layer of triangular 

 ligament. 



i. Constrictor urethra. 



K. Crus penis, cut. 



Arteries : 

 the 



in 



triangular 



a. Pudic, 

 ligament. 



b. Dorsal of penis. 



c. Cavernous. 



d. Deep muscular branch. 



Nerves : 



1 and 3. Dorsal of penis. 

 2. Perineal branch, giving offset 

 to bulb. 



of some veins, the fleshy fibres of the constrictor urethras will be 

 exposed. 



The CONSTRICTOR URETHRA (fig. 94, i) extends transversely across Constrictor 

 the sub-pubic arch, enclosing the membranous part of the urethra in ur 

 the same way as the sphincter ani externus surrounds the end of the 

 rectum. The muscle is attached by tendinous bundles on each side attach- 

 to the rami of the pubis and ischium, and other fibres spring from the m 

 two layers of the triangular ligament. Between these attachments disposition 

 the fleshy fibres are directed transversely and obliquely across the 

 middle line, one set passing in front of, and another behind the 



