APPENDIX. 189 



mucous membrane, thin and having longitudinal folds ; 

 an erectile envelope or corpus spongiosum, covering the 

 extra pelvic portion only ; muscles, represented by that 

 of Wilson, the bulbo-cavernous or accelerator nrinse, 

 the ischio-urethral or compressor urinse and the trans- 

 verse perinei. Blood vessels, the two dorsal arteries of 

 the penis and nerves from the internal pudic and great 

 sympathetic. 



Perineal aponeurosis. — Divided into superior and 

 deep layers. 



Glands annexed — prostate. — Situated in the pelvic 

 cavity at the commencement of the urethra ; a con- 

 glomerated gland whose secretion is thrown into the 

 urethra. 



Cowper's glands — OR SMALL PROSTATE. — Situated on 

 each side of the urethra, above the ischial arch, and 

 covered by the muscles of Wilson and ischio-urethral. 



Corpus cayernosum. — Erectile stalk, base of the 

 penis and support of the urethra. Situated between 

 the thighs, prolonged beneath the abdomen, attached 

 to the ischial arch and terminating by the glans penis. 

 External conformation : it offers two lateral faces 

 plane ; a superior or dorsal border rounded ; an infe- 

 rior or urethral channeled for the reception of the 

 urethra ; a posterior extremity with two roots or crura 

 attached to the ischial arch, and covered by the erector 



