Karl Rudolphi, Swedish naturalist. Historical artwork of Karl Asmund Rudolphi (1771-1832). Rudolphi is credited with being the father of helminthology, the study of worms. He worked widely across a number of fields including botany, zoology, anatomy and physiology. He investigated the anatomy of nerves, carried out studies of plant growth and was an early champion of the view that the cell is the basic structural unit of plants. He published a number of books on parasitic worms and was the first to describe the nematodes.