Hart describes the adult Santos in full, and accompanies his article with an illustration.

At this time he was said to have developed double genitals, and possibly a double bladder communicating by an imperfect septum.

At adulthood the anus was three inches anterior to the os coceygeus.

In the sitting or lying posture the supernumerary limb rested on the front of the inner surface of the lower third of his left thigh.

He was in the habit of wearing this limb in a sling, or bound firmly to the right thigh, to prevent its unseemly dangling when erect.
The perineum proper was absent, the entire space between the anus and the posterior edge of the scrotum being occupied by the pedicle.
Santos' mental and physical functions were developed above normal, and he impressed everybody with his accomplishments.
Geoffroy-Saint-Hilaire records an instance in which the conformation was similar to that of Santos.