This correspondence is chiefly to William Bartram concerning personal matters and birds.

These letters relate to natural history and birds.

These reels include letters to George Ord in Pennsylvania (1830-1869) and letters to Charles Edmonstone and sisters-in-law Eliza and Helen Edmonstone. There are also extracts of four volumes of observations on birds recorded by Norman Moore (1862-1871) and letters to Moore.

The naturalist Spencer Fullerton Baird worked as Assistant Secretary and Secretary of the Smithsonian Institution from 1850 until his death in 1887. A prolific collector and writer, Baird made important contributions to American ornithology, mammalogy, and herpetology, completing three monumental works, The Mammals of North America (Philadelphia, 1859), Birds of North America (Philadelphia, 1860), written with John Cassin, and History of North American Birds (Boston, 1874-1884), 5 vols., with Brewer and Robert Ridgway. The Baird Collection includes twelve letters written by Baird to the Boston printing firm, Welch, Bigelow and Co., all regarding editorial details in printing of the History of North American Birds.

This volume, written between May 3 and December 2, includes essays on mineralogy, the vegetable kingdom (such as botany and fruitification), and the animal kingdom (such as zoology, ornithology, and generation of animals).

This material relates to Alexander B. Grosart's biography of Wilson. There are notes and copies of letters and documents, including a copy of Wilson's will. There is one poem by Wilson, "The Last Wish," and an 1806 letter to William Bartram.

The primary correspondence (ca. 65 letters) is with William Cooper (1798-1864) on Bonaparte's publications, especially "American Ornithology" and "Observations on the Nomenclature of Wilson's Ornithology," but also included are many references to American and European men of science and learned societies. There are also letters to Isidore Geoffroy Saint-Hilaire, George Robert Gray, Titian Ramsay Peale, and Wilhelm P. S. Rüppell.