Adolf Engler

Heinrich Gustav Adolf Engler was a German botanist. He worked on plant taxonomy and phytogeography, such as Die natürlichen Pflanzenfamilien, edited with Karl A. E. von Prantl. His system of plant classification, the Engler system, is still used by many herbaria and is followed by writers of many manuals and floras. It is still the only system that treats all 'plants' in such depth.

Excerpt from Wikipedia, available under CC BY-SA 4.0.