In 1672, physician and anatomist Reinier de Graaf published his De mulierum organis about the female reproductive organs, with anatomically correct prints by Hendrik Bary, and some with little jokes. De Graaf was the first to conclude that a foetus was the product not just of a man’s seed, but also of a woman’s egg. He discovered what he called blisters, which later became known as Graafian follicles.