These papers include two pages by Rubens Peale concerning landscapes, a notebook by Rembrandt Peale relating to the portrait of Washington, and a commonplace and recipe book, with sketches of gas lights.

This volume contains medical notes by Wistar, including observations on yellow fever and arguments to prove its foreign origin, facts relative to the progress of the fever in 1797, the infection and death of Colonel Van Emburgh, the infection of the crew of the ship "Deborah" and of the Durham boat (1802), an account of the diseases which afflicted the family of James Hammar in Montgomery County (Pa.), facts relating to the typhus fever of 1812-1813, case histories (1796-1803), temperature chart (1758-1759, 1760), and a thermometrical journal (1760-1765) kept by Charles Norris and copied by Wistar from notes in possession of Joseph Parker Norris.

These papers include diaries (1777-1782), expense books (1794-1804), notebooks, a commonplace book, drafts of essays, excerpts from minutes of Friends' Monthly Meeting, Tortola (1741-1761), newspaper clippings, sketches, and correspondence. Also included are letters and papers of Mrs. Thornton.

This is a diverse collection, including correspondence, drafts of letters, notes and notebooks (on biometric methods; tables and formulae; science, nature and method; coefficient and correlation; vitalism; Japanese language); commonplace book (1924); autobiography; and over one hundred folders of unpublished writings. The correspondence and other material covers a variety of topics, including biology, eugenics, evolution and natural selection, human heredity, paramecia, protozoa genetics, U.S. immigration policy. There is much on the Seventh International Congress of Zoology (1907); letters to his father and wives, and from students and colleagues on his seventy-fifth birthday, 1943 (1 v.); diplomas and certificates of membership; and photographs.