Series I. Research Materials consists of two subseries. Subseries A. Tribes includes field notes, sources, maps, photographs/negatives, drawings, ephemera, and correspondence from tribal members and informants, and has been organized alphabetically according to tribal affiliation to the best extent possible. Tribes with a greater volume of research material have been categorized separately, and tribes with fewer materials have been included in the subsection "Other Tribes." Due to the nature of the field, there is some overlap in the material with regard to tribe, particularly between tribes that share the same language family, territory, or cultural traits. These intersections in the research material are also a reflection of Speck's method of study, as he often worked with more than one tribal group at a time. Further to Speck's process in the field, much of the information in this series is written down or drawn on small scraps of paper, on the backs of printed pages, in notebooks and in small notations on maps. Some photographs included in this subseries have been classified as culturally sensitive and restrictions on reproduction have been applied to these materials. Citations and copies of excerpts from secondary sources related to specific tribes and Speck's area of interest are also included in this research material. Subseries B. Other Research Material consists of material that is not directly related to Speck's fieldwork with tribal groups. Included are notes and drawing studies of Native American collections from North American and European museums, likely done by Speck's colleague, Marius Barbeau, and notes, citations and sources, guidebooks, draft manuscript pages, and correspondence related to Speck's natural history, general arts, and anthropological research.