
David Horsfall Stuart Richardson is a British and Canadian lichenologist noted for his studies on the effects of air pollution upon lichens. Richardson was awarded a doctorate from the University of Oxford for his thesis entitled Studies in the biology and physiology of lichens with special reference to Xanthoria parietina (L.) Th. Fr. Richardson was a professor at Trinity College, Dublin, Ireland before transferring to Saint Mary's University, Halifax, Nova Scotia, Canada. Until July 2006, he served as Dean of Science at St. Mary's University for numerous years.
(fr Wikipedia)