Root of penis

In human male anatomy, the radix (/reɪ.dɪks/; pl.: radices) or root of the penis is the internal and most proximal portion of the human penis that lies in the perineum. Unlike the pendulous body of the penis which is suspended from the pubic symphysis, the root is attached to the pubic arch of the pelvis and is not visible externally. It is triradiate in form, consisting of three masses of erectile tissue; the two diverging crura, one on either side, and the median bulb of the penis or urethral bulb. Approximately one third of the penis is embedded in the pelvis and can be felt through the scrotum and in the perineum.