MINISTERE DE L’EDUCATION NATIONALE CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE May 31, 1957 LABORATOIRE DE GENETIQUE PHYSIOLOGIQUE GIF-SUR-YVETTE (SEINE-ET-OISE Téx. : 136 a GIF Professor J, Lederberg Department of Genetics University of Wisconsin Madison, Wisconsin U.S.A. Dear Josh, I am pleased to inform you that the strain B-26, which I sent you some time ago, still contains the recessive gene (r) for "petiteness", Hawthorne juste completed the analysis of a few asci of the cross : petite B-26 x grande, and fo a2: 2 segregation in most of the asci, as in our previous work (Chen, Ephrussi and Hottinguer, Heredity, 1950). I shall be pleased to know what the present status of Wright's work and his further plans are. You intended to write to me about this. I suppose that your own plans for the future occupied most of your attention since your visit here, Is it too early to ask you what decision you have taken? With kindest regards, be ba ya Boris EPHRUSSI