NOV 2 6 19693 MEDICAL RESEARCH COUNCIL ev 26 wid We bs ws Telegrams: ‘NATINMED, LONDON, N.W.7. Telephone: MILL HILL 3666 NATIONAL INSTITUTE FOR MEDICAL RESEARCH, MILL HILL, LONDON, N.W.7. PRIVY COUNCIL 22nd November, 1963 Dear Joshua, I am terribly sorry to have been so long in arranging to send you the Census Fertility reports which contain extensive data on cohort analysis of fertility, and on patterns of family building etc. The machinery is in motion, and I hope it won't be too long before the documents arrive. I did enjoy my visit with you enormously - it was, in fact, the highlight of my sortie into California. Yours ever, () an Le cust, Dr. Joshua Lederbers, Department of Genetics, Stanford University, Palo Alto, California, United States of America.