eee ISTITUTO DI MICROBIOLOGIA E FISIOLOGIA VEGETALE UNIVERSITA DI PAVIA VIA SANT’EPIFANIO, 14 te, 27100 PAVIA (Italy) Prof. J. LEDERBERG The Rockfeller University 1230. York Avenue NEW YORK NY10021 Dear Josh, Many thanks for your letter concerning our "dottorato di ricerca". We have just started the first bureaucratic steps towards its establishment and I am sure that your letter will provide a consi- derable support. We are very sorry to hear of your illness and we really hope that your convalesgeen@and recovery are very quick. It is possible to I shall pass though New York during the first part of June (Gordon Conference). If such were the case, I shall look you and ascertain "de visu" the return to your prime. Best wishes and best regards from all of us. Yours sincerely, Le. Orio Ciferri