This investigation was aided by grants from The Jane Coffin Childs Memorial Fund for Medical Research, from The Rockefeller Foundation, and from Mr. Adolfo Eastman of Limache, Chile. These grants were administered by Professor A. Lipschütz.
Crystalline estradiol was supplied by Dr. Carl Miescher, of the firm of Ciba in Basel. Estrone, estriol, and equilenin were supplied by Dr. Oliver Kamm, of Parke, Davis & Co.
The senior author is responsible for the interpretation of results and preparation of the manuscript.