The papers consist of correspondence, journals and diaries, writings, legal and financial papers, and miscellanea of the William Dwight Whitney family, including William Dwight Whitney (1827-1894), his wife Elizabeth Wooster Baldwin Whitney (1824-1912), his brother Josiah Dwight Whitney (1819-1896), and his father Josiah Dwight Whitney (1786-1869). William Dwight Whitney material includes several hundred letters with his wife, journals and diaries (1843-1893), and a small quanity of professional papers. Material of his brother Josiah includes a geological survey of the Upper Mississippi (1862), and correspondence relating to the first systematic exploration and mapping of the American West. Information relating to Benjamin Silliman and the National Academy of Sciences is also documented. His family correspondence includes several hundred letters with William Dwight Whitney and their father, Josiah.