Oswald Heer (August 31, 1809 September 27, 1883), Swiss geologist and naturalist, was born at Niederuzwil in Canton of St. Gallen and died in Lausanne. He was educated as a clergyman at Halle and took holy orders, and he also graduated as Doctor of Philosophy and medicine. Early in life his interest was aroused in entomology, on which subject he acquired special knowledge, and later he took up the study of plants and became one of the pioneers in paleobotany, distinguished for his researches on the Miocene flora. In 1851 he became professor of botany in the university of Zürich, and he directed his attention to the Tertiary plants and insects of Switzerland. For some time he was director of the Botanical Garden Zürich.