Includes correspondence, autobiographical notes, addresses, articles, and drawings. The collection reflects Riddle's interests in breeding, heredity, and evolution. He was interested in humanism and the presentation of biological and evolutionary theories. There is much information on Riddle's activities in favor of freedom of scientific teaching, especially in high schools.

Letters (including some transcripts and photostats) from and to Vaughan from many American and British correspondents, including: Also personal correspondence and business papers of Benjamin, Charles, Petty, Samuel Sr., Samuel Jr., William, William Oliver, and Sarah Vaughan (2 boxes); lectures, mostly in shorthand (3 vols.); a large number of notes and memoranda on a wide variety of topics, such as agriculture, architecture, astronomy, diplomacy, diseases, dueling, electricity, hieroglyphs, internal improvements, medicine, meteorology, land, manufactures, politics, punctuation, religion, silk-manufacturing, stock-breeding, taxation, Unitarianism, Benjamin Franklin, John Locke, Napoleon I, Joseph Priestley, Bowdoin College, town of Hallowell, Maine; notes on the peace negotiations, 1782-1783; miscellaneous legal papers; genealogy of the Abbott-Vaughan families. For a personal account of the collection, see Mrs. Mary Vaughan Marvin, "The Benjamin Vaughan Papers," APS Proceedings 95 (1951): 246-249.

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.