WITH the passing of Burton Edward Livingston early this year, plant physiology in the United States has lost a distinguished figure. Himself an indefatigable investigator, he devoted much time and energy to the stimulation of scientific research and the promotion of co-operation and intercourse among his fellow men of science. From 1920 onwards he was a member of the executive of the American Association for the Advancement of Science, for fourteen years as secretary, and became its chairman in 1941. He served on the National Research Council. Among many other activities he took a prominent part in the foundation, in 1924, of the American Society of Plant Physiologists ; he was elected one of its first vice-presidents and was the first to be elected life member under the Charles Reid Barnes Foundation. The esteem in which the Society held him as an investigator was very appropriately indicated when in 1946 it conferred on him the Stephen Hales Award, since his chosen field Was the quantitative study of the water relations of plants, in which Stephen Hales was the pioneer.