LUFTPOST PAR AVION International Salmonella & Escherichia Center STATENS SERUMINSTITUT DIRECTOR: J. ORSKOV, M.D. TELEPHONE: ASTA 2817 TELEGRAMS: STATSSERUM, COPENHAGEN COPENHAGEN S. — DENMARK Copenhagen 14th November, 1958. Professor Dr. J. Lederberg Department of Genetics University of Wisconsin Madison 6, Wisc. U.S.A. Dear Dr. Lederberg: In answer to your letter of November 10th I can tell you that I had asked Professor Westphal some months ago whether I could send to you the preliminary table of E.coli results and strains which are Galactose-negative. He answered that they want to test these strains again, but did not say anything about the table. I have heard nothing on these strains and will write again to him. Yours sincerely, thf F Kauffmann