Correspondence primarily with Arthur A. Allen relating to Stuart's interest in ornithology, especially bird photography, including letters relating to the Life Magazine photo-essay contest; correspondence with Allen, Gustav Swanson, and others relating to the Laboratory of Ornithology Council, to Lab operations, funding, and publishing projects; Council minutes; and correspondence with Peter Paul Kellogg about bird recordings published by the Lab.

Correspondence, reports, manuscripts of articles, photographs, clippings, notes, memoranda, and printed material relating to Kellogg's career in the Laboratory of Ornithology at Cornell University; the history of the Laboratory; the Albert R. Brand Bird Song Foundation; ornithological expeditions to central Africa, Manitoba, and elsewhere; and bird clubs.