The letters to Persifor Frazer cover primarily matters related to geology and mineralogy. A portion of the correspondence, principally from British scientists, concerns the 1884 meeting in Philadelphia of the American Association for the Advancement of Science (B F867).

Mostly concerned with Blakeslee's studies on beans, blood groups, colchicine, Datura, embryo cultures, and horticulture. Many letters relate to the support and direction of the Smith College Genetics Experiment Station, which he headed. Other letters are about the Carnegie Institution of Washington, "Biological Abstracts," American Association for the Advancement of Science, American Philosophical Society, Institut de France, University of Connecticut. Also contains travel letters from Germany and miscellaneous lectures.

Britton Chance (1913-2010) was a biochemist and biophysicist as well as a pioneer in the field of biomedical optics. Chance received his Ph.D. in Physical Chemistry from the University of Pennsylvania in 1940 and his Ph.D. in Biology and Physiology from Cambridge University in 1942. Over the course of his nearly eight decade career, Chance was dedicated to the application and transfer of basic scientific research and technology to clinical medicine. The Britton Chance Papers contain correspondence, research notes, experimental data, publication materials, and photographs stemming from Chance's life as a biochemist, biophysicist, and yachtsman. The collection is broken up into fifteen series that document every aspect of his scientific work.

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.