TRANSVERSUS PERINEI. 



ing it as in a sling, as described by Mr. Wilson, but merely an upper 

 origin of the transverse muscle. 



Fig. 119* 



The compressor urethras may be considered either as two symmetrical 

 muscles meeting at the raphe, or as a single muscle : I have adopted the 

 latter course in the above description, as appearing to me the more con- 

 sistent with the general connexions of the muscle, and with its actions. 



The TRANSVERSUS PERINEI arises from the tuberosity of the ischium 

 on each side, and is inserted into the central tendinous point of the 

 perineum.! 



Relations. By its superficial surface with the superficial perineal fascia, 

 and superficial perineal artery. By its deep surface with the deep perineal 

 fascia, and internal pudic artery and veins. By its posterior border it is 

 in relation with that portion of the superficial perineal fascia which passes 

 back to become continuous with the deep fascia. 



To dissect the compressor urethra, the whole of the preceding muscles 

 should be removed, so as to render the glistening surface of the deep peri- 

 neal fascia quite apparent. The anterior layer of the fascia should then 

 be carefully dissected away, and the corpus spongiosum penis divided 

 through its middle, separated from the corpus cavernosum, and drawn 

 forwards, to put the membranous portion of the urethra, upon which the 

 muscle is spread out, on the stretch. The muscle is, however, better 

 seen in a dissection made from within the pelvis, after having turned 



* The muscles of the perineum. 1. The acceleratores urinse muscles; the figure rests 

 upon the corpus spongiosum penis. 2. The corpus cavernosum of one side. 3. The 

 erector penis of one side. 4. The transversus perinei of one side. 5. The triangular 

 space through which the deep perineal fascia is seen. 6. The sphincter ani ; its ante- 

 rior extremity is cut off. 7. The levator ani of the left side ; the deep space between 

 the tuberosity of the ischium (8) and the anus, is the ischio-rectal fossa; the same fossa 

 is seen upon the opposite side. 9. The spine of the ischium. 10. The left coccygeu* 

 muscle. The boundaries of the perineum are well seen in this engraving.' 



f- I have twice dissected a perineum in which the transversus perinei was of large 

 size, and spread out as it approached the middle line, so as to become fan-shaped. The 

 posterior fibres were continuous with those of the muscle of the opposite side ; but tha 

 anterior were prolonged forwards upon the bulb and corpus spongiosum of the urethra, 

 as far as the middle of the penis, forming a broad layer which usurped the place ar.i? 

 office* of the accelerator urinae. 



19* 



