Pasteur Award Lecture at meeting of Society of Illinois Bacteriologists, 27 May 1961. The Pasteur Award has been given each year by the Society of Illinois Bacteriologists to a person in the Midwest. Past recipients are: I. Forest Huddleson (1948), Stewart A. Koser (1949), Jacques J. Bronfenbrenner (1950), Chester H. Werkman (1951), Salvador E. Luria (1952), Howard J. Shaughnessy (1953), James A. Reyniers (1954), Perry W. Wilson (1955), Joshua and Esther Lederberg (1956), Gail M. Dack (1957), Carl C. Lindegren (1958), Lloyd B. Jensen (1959), Halvor Orin Halvorson (1960), and Fred W. Tanner, Sr. (posthumously). The award includes the silver medal shown: