William E. Castle '93, professor of Genetics since 1908 and one of the foremost American zoologists, has retired from the Faculty and will become professor-emeritus next September. For many years the Executive Officer of the Bussey institute for advanced research in applied biology, Professor Castle is 69 years old.

Professor Castle is widely known for research in animal genetics extending over a period of more than forty years. His publications in this field include "Heredity in Relation to Evolution and Animal Breeding" (1911), "Genetics and Eugenics" (1916), and several papers on subjects of heredity and evolution.

Ils is a research associate of the Carnegie Institute of Washington, and a member of numerous societies. He has received honorary degrees from Denison University, and the University of Wisconsin.