An archaeological anthropologist and linguist, John Alden Mason spent the majority of his career at the University Museum of the University of Pennsylvania. After receiving his undergraduate degree at Penn in 1907, Mason received a doctorate at Berkeley (1911) for his ethnographic work on the Salinan Indians of California, but his diverse interests in later years ran the gamut from Puerto Rican folklore to Piman languages and cultures (including Pima, Papago, Pima Bajo, Northern and Southern Tepehuan, and Tepecano), Mayan, Aztec, and Incan archaeology, and the languages of South American Indians. Mason was curator of the University Museum at Penn from 1926 until his retirement in 1958. The Mason Papers include both in-coming and outgoing correspondence, linguistic material, notes, and photographs relating to Mason's work in the southwestern U.S., northern Mexico, and South America. Centered on the years after Mason's return to Philadelphia in 1926, the collection covers all aspects of Mason's professional life, from reports on field work to answering casual questions referred to him through the University Museum to data and analyses on Piman and other languages. The collection also contains voluminous files relating to the Mason's editorship of the American Anthropologist (bulk: 1945-1948). Of special note are a series of class notes (1908-1910) kept by Mason for course work in ethnology, archaeology, and linguistics at the University of Pennsylvania under Edward Sapir and Frank Speck.

Alfred Irving ("Pete") Hallowell was an anthropologist best known for his studies of Ojibwa culture and world-view, and the innovative use of the Rorschach Test in his studies of the psychological interrelations of individuals and their culture. Early in his career, Hallowell worked as a social case worker for Family Service, and even after moving on to study anthropology in 1920 (M.A.), he carried with him an interest in ethnic and racial culture, developing additional interests in psychological testing. Except for the years 1944-1947, when he taught at Northwestern University, Hallowell spent his entire career at the University of Pennsylvania where he was professor of anthropology, professor of anthropological psychiatry in the Medical School, and curator of social anthropology at the University Museum. A cultural anthropologist, Hallowell's use of clinical psychological methods, especially Rorschach tests, was both innovative and controversial in his discipline. In his research, he concentrated on the Algonkian Indians, especially the Abenaki and Ojibwa Indians of Canada and Wisconsin (Berens River, Lake Winnipeg, Manitoba, and Lac du Flambeau, Wisconsin areas), and the Saulteaux of Berens River. The Alfred Irving Hallowell Papers (1892-1981) contain correspondence, subject files, manuscripts of published and unpublished works by Hallowell, papers by colleagues and students, research notes kept by Hallowell, with a special emphasis on social organization, personality, behavior, psychology, religion, and folklore. The collection of several hundred photographs provides rich graphic documentation of Hallowell's work among the Ojibwa and Abnaki Indians during the 1930s.