Because the anatomical position of the penis is erect, the paired corpora are defined as dorsal in the body of the penis and the single corpus spongiosum as ventral, even though the positions are reversed in the nonerect (flaccid) penis.
The corpus spongiosum expands to form the head of the penis (glans penis) over the distal ends of the corpora cavernosa (Fig. 5.71B).