©Wellcome Library, London

The flower of the opium poppy, possibly the most powerful medical icon of the plant kingdom. This particularly beautiful illustration is reproduced from a copy of Dioscorides' De materia medica, made in c. 512 CE at Constantinople for Princess Anicia Juliana, daughter of Olybrius, one of the last Roman emperors.

Source: Codex Aniciae Julianae picturis illustratus, nunc Vindobonensis med: Gr I. AW Sijthoff, Leiden 1906.