Photomicrographs of elastic system fibers in the corpus cavernosum and corpus spongiosum (brown tint) of fetal penis at different ages in weeks post-conception (WPC).

<p>A) Corpus cavernosum, fetus of 13 WPC; B) Corpus spongiosum, fetus of 13 WPC; C) Corpus cavernosum, fetus of 20 WPC; D) Corpus spongiosum, fetus of 20 WPC; E) Corpus cavernosum, fetus of 30 WPC; F) Corpus spongiosum, fetus of 30 WPC. Immunostaining for elastin, X1000.</p>