252 DISSECTION OF THE PERINEUM. 



that they are the pointed posterior extremities of two dense cylindrical 

 tubes of fibrous tissue (the corpora cavernosa) containing erectile* 

 tissue, which blend about an inch and a half from their posterior 

 extremities to form the body of the penis. A slight enlargement 

 will be noticed on each crus, which has been called the bulb of the 

 corpus cavern osum (Kobelt). The structure of the corpora cavernosa 

 will be seen at a later stage. 

 Bulb of The BULB OF THE URETHRA is an enlargement of the vascular and 



lia ' erectile tissue (the corpus spongiosum) which surrounds the urethra 

 from the triangular ligament onwards. The bulb is firmly united to 

 the under surface of the triangular ligament and usually presents a 

 slight central depression, with a bulging on each side forming two 

 lateral lobes. 



Tegumen- CUTANEOUS COVERINGS OP THE PENIS AND SCROTUM. The peilib 



in^of "penis ^ s attached to the front of the pelvis by a suspensory ligament, and 



is thin, and i s provided with a tegumentary covering continuous with that of the 



without fat, -iff 4. 



abdomen, but devoid ol fat. 



Around the end of the penis it forms the loose sheath of the 

 prepuce in the following way : When the skin has reached the 

 extremity, it is reflected backwards as far as the base of the glans, 

 forms constituting thus a sheath with two layers the prepuce ; it is after- 



prepuce, wards continued over the glans, and joins the mucous membrane ol 

 the urethra at the orifice on the surface. At the under part of the 

 glans and behind the aperture of the urethra, the integument forms 

 and fr*num. a small triangular fold, frcenum prceputii. 



Sebaceous Where the skin covers the glans, it is inseparably united with 

 that part, is very thin and sensitive, being provided with papillae, 

 and assumes in some cases the characters of a mucous membrane. 

 Behind the glans are some sebaceous follicles yhnidulce odorifene. 

 Teguments J^j, the scrotum the two layers of the superficial fascia of the groin 

 become united in a thin membrane of a reddish colour. The pro- 

 longation around the testicle on one side is separate from that on the 

 other side ; and the two pouches, coming in contact in the middle 

 line, form the septum scroti. 



Muscular The subcutaneous layer in the scrotum, penis, and front of the 

 fascia 8 perineum contains involuntary muscular fibres, to which the corru- 

 gation of the skin is owing. This contractile structure is named 

 the dartoid tissue. 



Dissection Dissection, The scrotum should now be accurately divided into 

 and Serves ^ wo na l yes ^J an incision in the middle line and each half containing 

 its testis is to be held aside. The incision should be continued 

 along the under surface of the penis to the framum and the skin of 

 the organ dissected off as a sheath. The staff is to be removed from 

 the urethra and the fatty tissue from the root of the penis and the 

 front of the symphysis pubis should be removed so as to define the 

 suspensory ligament. The dorsal arteries and nerves, with the 

 dorsal vein of the penis, which will be laid bare, are to be 

 followed forwards to the glans. 

 Suspensory The suspensory ligament of the penis is a band of fibrous tissue 



