This collection includes correspondence, manuscripts (lectures and articles), research grant material, research data, and participation in organizations, such as, the American Society of Naturalists (President, 1968), Genetics Society of America (President, 1963), and the National Research Council. Of particular note, are the detailed data related to Drosophila eye pigment, and human chromosomes.

L.C. Dunn was one of the most significant figures in the emerging field of developmental genetics in the 20th century. His T-locus work with the mouse established a number of important genetic principles, including ideas of gene interaction, the distribution of alleles in wild populations, and the factors that influence fertility. He wrote an important textbook of genetics, Principles of Genetics (1925), in collaboration with Sinnott (and later Dobzhansky); other significant books authored or co-authored by him include Heredity, Race and Society (1946), and A Short History of Genetics (1965). He worked in poultry genetics for eight years at the Agricultural Experiment Station in Storrs, CT, from 1920-1928. The remainder of his career was spent at Columbia University, where he worked with rats, mice, and fruit flies, and proved himself to be an inspiring teacher as well. His interest in international scientific collaboration led him to establish ties to Soviet scientists, and to help relocate refugee scientists during World War II. He remained active in his profession to the end of his life. This collection includes correspondence, reports, notebooks, lectures, and photographs. It is a rich collection, documenting the development of American genetics as well as Dunn's interests in humanitarian efforts and international affairs. There is significant material relating to American-U.S.S.R. contacts, particularly in the files on the American-Soviet Friendship Council and the American-Soviet Science Society. There is much, as well, on the impact of the Lysenko controversy in the U. S. Dunn's interest in European scientists can also be seen in the sizable amount of material on the Emergency Committee in Aid of Displaced German Scholars. Material relating to the Kilgore and Magnusson bills for the support of science (predecessors to the NSF) are also in the collection. Of note are data on the following: National Research Council Committee on Experimental Animals and Plants; research on the population study of the Jewish community in Rome; and Columbia University. There is much in the correspondence concerning Drosophila, poultry genetics, and other such topics; Walter Landauer is Dunn's major correspondent.

The geneticist Milislav Demerec emigrated from Yugloslavia in 1919, spending nearly his entire career in the Department of Genetics at Cold Spring Harbor Laboratory. Working initially on the genetics of maize and later on Drosophila virilis, his research interests included radiation and chemical mutagenesis, and during the Second World War, penicillin and the genetics of antibiotic resistance. Demerec served as head of the laboratory at Cold Spring Harbor from 1941 until 1960. The Demerec collection contains the extant professional papers of Milislav Demerec, dating primarily from the time of his arrival at Cold Spring Harbor until his retirement. In addition to his correspondence with colleagues, the collection includes interesting material on the administration of Cold Spring Harbor laboratory during the 1940s and 1950s, data and research notes, material relating to professional organizations (e.g. Genetics Society of America, American Society of Naturalists), a lengthy series of lectures given by Demerec, and a large number of photographs pertaining to Demerec's research, but also to his colleagues and Cold Spring Harbor itself. There is also a Register of visitors to the laboratory (1927-1945) and a Milislav Demerec reprint list.

Between 1968 and 1978, the historian of science Horace Freeland Judson conducted extensive oral history interviews with biochemists and molecular biologists relating to the development of their field. The correspondence, transcripts of interviews, and taped interviews that comprise the Judson collection formed the research material used by Judson in his book, The Eighth Day of Creation (New York, 1979). Permission to quote must be obtained from Dr. Judson and access to some files is restricted.