THE PERINEUM 385 



The passage of a rigid instrument. No. 8 or 9, along a healthy 

 urethra into the bladder presents no difficulty, if its point is 

 kept in contact with the roof of the urethra after the fossa 

 navicularis has been traversed. When a small instrument is 

 used, some difficulty may be experienced in passing from the 

 bulb into the membranous urethra as, unless the point is kept 

 along the roof of the canal, it impinges against the urogenital 

 diaphragm just below the urethral opening. In these cases, 

 the instrument should be withdrawn for a short distance and 

 then the handle should be depressed so that the point may rise 

 towards the orifice in the diaphragm. 



The Body of the Penis consists of the two corpora cavernosa, 

 which lie side by side on the dorsum, and the corpus cavernosum 

 urethra (c. spongiosum), which lies in the groove separating the 

 two corpora cavernosa ventrally. At its termination, the 

 corpus cavernosum urethrae expands into a conical enlargement, 

 termed the glans penis, which projects dorsally and laterally, 

 so as to cover the extremities of the corpora cavernosa. 



The component parts of the penis contain numerous venous 

 spaces, in which the blood may be retarded by the contraction 

 of the ischio-cavernosi and the bulbo - cavernosus (p. 377), 

 leading to enlargement of the organ. In conditions of 

 gonorrhceal inflammation, the spaces in the corpus cavernosum 

 urethrae, being already rilled with serous exudate, fail to distend, 

 when the corpora cavernosa are undergoing distension. As a 

 result, the penile erection is not straight but is curved, owing 

 to the inelastic condition of the corpus cavernosum urethrae. 

 This constitutes the condition which is known as chordee. 



The skin of the penis is very thin, and is freely movable over 

 the body of the organ. At the extremity of the penis it is 

 folded back to form a hoodlike covering for the glans. This is 

 termed the prepuce its deep surface is lined by modified skin, 

 which is reflected on to the glans (i) at its base, the corona 

 glandis, and (2) on its ventral aspect, where it forms the frenulum. 

 The modified skin covering the glans is firmly adherent, and 

 contains sebaceous glands, which secrete the smegma. The 

 latter collects in the region of the corona glandis, and may 

 sometimes form concretions. 



In the condition of Phimosis there is a long narrow prepuce, 

 which cannot be drawn back off the glans. Adhesions between 

 the deep surface of the prepuce and the skin surface of the glans 

 may give rise, reflexly, to urinary disturbances. The whole 



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