The fibrous envelope of the corpus cavernosum urethræ is thinner, whiter in color, and more elastic than that of the corpora cavernosa penis. It is called the trabeculae of corpus spongiosum of penis.

The trabeculæ are more delicate, nearly uniform in size, and the meshes between them smaller than in the corpora cavernosa penis: their long diameters, for the most part, corresponding with that of the penis.

The external envelope or outer coat of the corpus cavernosum urethræ is formed partly of unstriped muscular fibers, and a layer of the same tissue immediately surrounds the canal of the urethra

Urethra

In anatomy, the urethra is a tube that connects the urinary bladder to the genitals for the removal of fluids out of the body. In males, the urethra travels through the penis, and carries semen as well as urine...

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