Senior Research fellow, Morgan Library; medieval manuscripts specialist. Plummer received his A.B. from Carleton College, Northfield, MN. He entered Columbia University in 1944, studying medieval art under Meyer Schapiro. As a graduate student, he taught art history courses. His lectures sparked the interest of Lucy Freeman Sandler to be a manuscripts scholar. He received his Ph.D. in 1953 with a dissertation on a thirteenth-century English Illuminated Bible.