He wrote some very interesting letters to one of his friends who was J.D. Hooker, or at that time, president of the Royal Society, so the maximum scientific authority in Britain speaking about the brain in the plants.
Darwin scrisse alcune lettere molto interessanti all'amico J.D. Hooker, a quel tempo Presidente della Royal Society, quindi la massima autorità scientifica in Inghilterra, e gli parlò del cervello delle piante.