This miscellaneous collection relates to numerous topics in genetics: cattle breeding (especially the American Jersey Cattle Club), longevity, radiation, International Congress of Genetics (the 10th, 11th, and 13th), Gregor Mendel, aid for refugee scientists, and the records of the Genetics Society of America (1947-1974). The photographs series accession # 1968 433pr, was added to the finding aid in 2016.

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.

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.

Founded in 1931, the Genetics Society of America works to facilitate communication among scientists with an interest in research and education in genetics and cognate fields. The GSA Records provide information on the history of the Genetics Society of America from the time of its founding in 1931. Included is correspondence between various officers, members, and outside individuals and organizations, files on standing and ad hoc committees, Records concerning accounts and finances, membership data, files relating to annual meetings, local meetings, and international meetings, and information on special commissions or ad hoc groups of the Society. Among the more noteworthy files are those for the Committee on Genetics, Race, and Intelligence, 1974-1975. This note is currently under review for revision.

The population geneticist Hampton L. Carson spent the major part of his career at Washington University (1949-1963) and the University of Hawaii (1963-1985) investigating the cytogenetics and evolution of Drosophila. As one of the major figures in the Hawaii Drosophila project, he made particularly important contributions to the study of speciation and selective and non-selective evolutionary mechanisms. The Carson Papers (1921-1993) contain correspondence, subject files, manuscripts of published and unpublished works by Carson, papers by colleagues and students, research notes, course materials, photographs, and biographical information, which documents Carson's career as an evolutionary geneticist. The collection is organized into nine series.

A bacteriologist from MIT, Salvador E. Luria's work with Max Delbruck on bacteriophage demonstrated that bacterial resistance to certain phages arose through genetic mutations. His later work showed that phages also mutate genetically. He received the Nobel Prize in Physiology or Medicine in 1969 with Max Delbruck and Alfred D. Hershey. The collection is organized into seven series: I. Correspondence, 1938-1992 ; IIa. Subject Files, 1938-1990 ; IIb. Personal Material. 1923-1991 ; III. Works by Luria, 1938-1987 ; IV. Works by Others, 1944-1990 ; V. Research Notes and Notebooks, 1941-1979 ; VI. Course Material, 1931-1991 ; VII. Photographs and Negatives, 1957-1982. Arrangement: Alphabetical by folder title and then chronological within each folder.

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.

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.