The papers contain correspondence, research and teaching notes, data (card and slip) files, published and unpublished manuscripts by Lounsbury and others, books and reprints, sound recordings, and computer programs and files. Correspondents include: William N. Fenton, Mary R. Haas, William C. Sturtevant, Morris Swadesh, and Carl F. Voegelin. Roughly one-quarter of the collection relates to Iroquoian languages and includes much WPA Oneida Project material. Research into the Cherokee language, South American languages, and kinship structures is also well represented. Floyd Lounsbury's wife, Masako Yokoyama Lounsbury, is represented by a smaller amount of material relating to linguistic research in Shanghai and research on Quechua.

The James V. Neel Papers document nearly every phase of the career of one of the founders of human population genetics in the United States. Neel was particularly thorough and organized, and retained virtually all of his significant scientific correspondence, committee reports, minutes of meetings, and drafts of manuscripts. The collection also includes data collected during Neel's work among the Xavante, Yanomanö and other indigenous populations. In a career that spanned the period from the late work of Thomas Hunt Morgan and Charles B. Davenport to the contemporary world of molecular genetics and nucleic acids, Neel knew, worked with, and corresponded with many of the most influential 20th century practitioners of genetics. The collection begins in earnest in 1943, after Neel had decided to focus on human genetics. Neel's work with Drosophila and none of his Drosophila manuscripts are found in the collection.