A modest Midwesterner who became one of the most influential geneticists of the first half of the 20th century, William E. Castle spent his career at Harvard and the University of California working on patterns of inheritance in mice, horses, and a variety of other mammalian taxa. An early proponent of Mendelian theory, Castle was director of the Bussey Institution at Harvard for almost thirty years, helping to train a number of important geneticists. The Castle Papers contain one linear foot of correspondence dating primarily from the period after Castle's "retirement" to Berkeley in 1936 until his death in 1962, dealing almost exclusively with his research on horse breeding and the inheritance of coat coloration in horses. Castle's correspondence with his former student L. C. Dunn is an exception, focusing on mouse genetics and ranging to a variety of topics from the conduct of scientific research during the Second World War to Castle's interests in the early history of genetics.

Leonard Carmichael was a psychologist whose most significant contributions were made in the fields of child psychology and biopsychology. Educated at Tufts and Harvard, he taught at Princeton, Brown, and Rochester, later returning to Tufts to serve as its President from 1938-1952. An outstanding administrator, Carmichael served as executive officer for the Smithsonian Institute from 1952-1964, and was subsequently vice president for research and exploration at the National Geographic Society. In his later years, he served as President of the American Philosophical Society from 1970-1973. This large and varied collection reflects the entire range of Carmichael's prolific career. It includes a variety of types of records, including correspondence, committee reports and records, long series of articles and speeches, drafts of papers and books, and pocket notebooks. All phases of his professional life are covered, from his years in academia, to his time at the Smithsonian Institute and the National Geographic Society, as well as his involvement in a large number of professional organizations.

A pathologist and cancer specialist, James B. Murphy (1884-1950) spent most of career associated with the Rockefeller Institute (1911-1950) investigating the role of lymphocytes in tuberculosis, x-ray mutagenesis, and the nature of malignant tumors in fowls. The Murphy Papers contains professional correspondence and research notes relating to James B. Murphy's cancer research at the Rockefeller, and information on several of the organizations to which he contributed or belonged, including the American Association for Cancer Research; American Bureau for Medical Aid to China; American Cancer Society; Bar Harbor Medical and Surgical Hospital; Roscoe B. Jackson Memorial Laboratory; Memorial Hospital for the Treatment of Cancer (New York City, ca. 1932-1950); National Advisory Cancer Council; and the New York Academy of Medicine (1923-1950). Murphy helped to develop mobile laboratories for hospitals in France during World War I.

Ernst Wolfgang Caspari was an important contributor to behavior and developmental genetics, working primarily on the mealmoth Ephestia. Trained in Alfred Kuhn's laboratory at the University of Göttingen (1933-1935), Caspari was forced from his position by the Nazis in 1933, escaping to the United States five years later. As a professor of biology at Lafayette College, Wesleyan University, and the University of Rochester, Caspari continued his research on Ephestia, mouse genetics, and behavior genetics until his retirement in 1975. The Caspari Papers includes correspondence, papers, grant reports, and lectures relating to Caspari's genetic research dating primarily from the period after his departure from Germany. In addition to substantial material on behavior genetics and human evolution, the collection includes correspondence relating to Caspari's editorial work for Advances in Genetics, and his involvement with the American Institute of Biological Sciences, the Center for Advanced Study in the Behavioral Sciences, Cold Spring Harbor Laboratory, Fifth Banff Conference on Theoretical Psychology, Genetics Society of America, International Conference on the Unity of Science, Social Science Research Council, Committee on Genetics and Behavior, and the U.S. Atomic Energy Commission.

Sewall Wright ranks among the most influential figures in the field of population genetics during the 20th century, and made important contributions to biostatistics, biometrics, and evolutionary theory. These papers contain much of Wright's professional correspondence, scattered research notes, and drafts of a small number of papers.

Founded by the Brooklyn Institute of Arts and Sciences in 1890, the Biological Laboratory at Cold Spring Harbor, N.Y., was little more than a languishing outpost until the arrival of Charles B. Davenport in 1898. Over the course of two decades, the ambitious young biologist used his extraordinary administrative skills to transform the institution into the premier center of eugenical study and, as its director, to position himself as the leading spokesman for eugenical research in North America. The Davenport Papers (ca. 63 lin. feet) is a large and nearly comprehensive body of correspondence, lectures, diaries (1878-1942, mostly brief entries of an uneven character), student notebooks and family correspondence pertaining to Charles Davenport and the Cold Spring Harbor Laboratory. The collection is divided into two series, the Charles Davenport Papers, which provides valuable documentation of the development of American biology, animal and plant genetics, and eugenics during the period 1898-1942, with some perspective on the international eugenics movement. Series II, the Cold Spring Harbor Records (ca.20 lin. feet), consists largely of administrative correspondence relating to the laboratory, including Davenport's correspondence with Carnegie administrators (esp. Robert Woodward and John Merriam), accounts and reports concerning financial matters, publications, salaries, material relative to the early history of Cold Spring Harbor labs, and records relative to the numerous professional assistants who worked under Davenport. Among the major correspondents are the American Breeders Association, Committee on Eugenics; American Eugenics Society; American Society of Naturalists; Committee on a Study of the American Negro; Galton Society (see also the extensive correspondence with William K. Gregory); Eugenics Education Society (see Mrs. S. Gotto correspondence); International Congresses of Eugenics; International Federation of Eugenic Organizations, Committee on Race Crossing; National Committee on Mental Hygiene; National Committee on Prisons and Prison Labor; and the Pan-American Conference on Eugenics and Homiculture. There are correspondence and papers relating to the Station for Experimental Evolution, the Eugenics Record Office, and the Carnegie Institution of Washington, and a substantial series relating to a long-range study of children carried out at Letchworth Village, Thiles, New York. This note is currently under review for revision.