American physician and botanist from Southampton, Massachussetts, of English parents, who trained at Amherst College and later moved to Florida where he practiced medicine (1835-1879). He eventually settled in Apalachicola (1847-) and actively pursued his interest in Botany, becoming a friend of Asa Gray and publishing a flora of southern United States. During the American Civil War, Chapman strongly supported the Union, but his wife was a Secessionist and they lived apart for the duration. Chapman claimed that he owed his life during the frequent raids to the fact that he was the only surgeon in the city and disease was rife. The University of North Carolina conferred an honorary degree upon him (1886) and he was elected an Associate Fellow of the American Academy of Arts and Sciences (1887) and an Honorary Member of the Botanical Society of America (1895). The genus Chapmannia Torr. & A. Gray and many species were named in his honour, including Liatris chapmanii Torr. & A. Gray and Rhododendron chapmanii A. Gray. Part of his herbarium was purchased by MO in 1899; other original material is at NY.