September 3, 1968 Howard Fields, M.D. Walter Reed Army Research Institute Neurophysiology Department Washington, D. C. 20012 Dear Dr. Fields: Your note of August 22 was especially gratifying especially coming from a former student here. It was kind of you to take the time to write. You would be surprised how few people do so when they have something to say as positive as you did. Sincerely yours, J. Lederberg Professor of Genetics JL/nla $474!