Swedish botanist Erik Acharius (1757–1819) is considered the father of lichenology. He was the founder of modern lichen taxonomy, having described and arranged lichens into forty distinct genera. His four major works of research—Lichenographi suecic prodromus (1798), Methodus lichenum (1803), Licheno graphia universalis (1810), and Synopsis methodica Lichenum (1814)—formed the foundations of modern lichenology.