Ray, John

English naturalist who devised a classification system accounting for some 18,000 plant species. It was the first system to divide flowering plants into monocotyledons and dicotyledons, with additional divisions made on the basis of leaf and flower characters and fruit types.

In Methodus plantarum nova (1682), Ray first set out his system. He also established the species as the fundamental unit of classification. Ray believed that fossils are the petrified remains of dead animals and plants. This concept, which appeared in his theological writings, did not gain general acceptance until the late 18th century.