WALTER H. LEWIS, PhD, DSc, is Professor Emeritus of Biology and University Research Ethnobotanist at Washington University in St. Louis, Missouri. He is also Senior Botanist at the Missouri Botanical Garden.
MEMORY P. F. ELVIN-LEWIS, PhD, DSc, is Professor of Biomedicine in Microbiology and Ethnobotany, and Adjunct Professor of Biology at Washington University in St. Louis, Missouri.