The Jane Coffin Childs Memorial Fund for Medical Research Board of Sctentific Advisers Office of Director S. BAYNE-JONES, Director Yale University School of Medicine RALPH G. MEADER, Assistant Director R J.A 333 Cedar Street UDOLPH J. ANDERSON Ross G. HARRISON New Haven 11, Connecticut JOHN J. MORTON PEYTON Rous GEORGE M. SMITH M. C. WINTERNITZ December 10, 1946 Mr. Joshua Lederberg Osborn Botanical Laboratory Yale University School of Medicine Dear Mr. Lederberg: Thank you for furnishing to the Fund twenty-six reprint copies of the following articles, which acknowledge aid from the Fund: Lederberg, Joshua and Tatum, E. L. Gene Recombination in Escherichia coli. Nature, October 19, 1946, 158, 558, Lederberg, Joshua. Studies in Bacterial Genetics. J. Bact., 52, 1946, 503. Sincerely yours, R. G. Meader rgm:em