Carte de visite photograph by Franz Neumayer of Munich, Germany. Originally training to become a doctor, Carl Wilhelm von Naegeli (1817-1891) gave up medicine to study botany, working first under Alphonse de Candolle (1806-1893) in Geneva, Switzerland and then Matthias Schleiden (1804-1881) at the University of Jena, Germany. In 1842 he became the first person to accurately describe cell division, including division of the nucleus. He also contributed to advancements in plant taxonomy and plant growth and was profesor of botany and director of the botanical garden at Munich University from 1857 to 1889.
© Science Museum / Science & Society Picture Library