If not noticed at birth, it is not usually discovered till adult life, and even then the discovery is commonly accidental.
3.

With regard to the functions of the pelvic viscera, urine may be passed by both penises, by one only, or by neither.

In the last instance it finds exit by an aperture in the perineum.

There is reason to believe that semen may be passed in the same way; but in most of the recorded cases there has been sterility, if not inability to perform the sexual act.
4.

All the degrees of duplication have been met with, from a fissure of the glans penis to the presence of two distinct penises inserted at some distance from each other in the inguinal regions.
5.