also served as president of the Garden History Society and the Ray Society (1975–1977). The Royal Horticultural Society had made him an honorary fellow in 1946 and in 1986 he became a vice-president. Stearn became a member of the Botanical Society of Britain and Ireland (BSBI) in 1954, joining the Maps Committee the following year to prepare their Atlas of the British Flora (1962). He remained on that committee till 1968, when it became the Records Committee. For 40 years he was the BSBI referee for Allium. While at the Lindley Library, he became a founding member of the Society for the Bibliography of Natural History (later, the Society for the History of Natural History) in 1936, was one of its most active publishing members based on his cataloguing work at the library, and published a history of the society for their 50th anniversary in 1986. Other societies on which he served include the British Society for the History of Science (vice-president), the British Society for the History of Medicine (Council), the Garden History Society (president 1977–1982) and was a corresponding member of the Botanical Society of America. Stearn was appointed Sandars Reader in Bibliography, University of Cambridge in 1965 and from 1977 to 1983 he was visiting professor at Cambridge University's Department of Botany, and also Visiting Professor in Botany at Reading University 1977–1983, and then Honorary Research Fellow (1983–). He was also a fellow of the Institute of Biology (1967) and was elected an Honorary Fellow of Sidney Sussex College, Cambridge in 1968. Work William Stearn was the author of nearly 500 publications, including his autobiography. These included monographs, partial floras, books on botanical illustration, scholarly editions of historical botanical texts, dictionaries, bibliographies and botanical histories. Early years During Stearn's initial four years in Cambridge (1929–1933), he published twenty-four papers, predominantly in the Gardeners' Chronicle and Gardening Illustrated and the Journal of Botany, his first in 1929. While working as a gardener's boy during school holidays he had observed a specimen of Campanula pusilla (Campanula cochleariifolia) with a distorted corolla. He then described and published the first appearance of the causative agent, the mould Peronospora corollaea, in Britain, using the facilities of the Botany library. At the Botanic Garden he developed a special interest in Vinca, Epimedium, Hosta and Symphytum, all of which he published monographs on. A series of botanical publications followed, starting with a new species