In 1909 he moved to the Field Museum of Natural History in Chicago, where he was assistant curator of mammalogy and ornithology from 1909 to 1921, and curator of zoology from 1921 to 1940. He collected in North America and Chile. He traveled with Louis Agassiz Fuertes to Ethiopia as part of the 1926-27 Field Museum-Chicago Daily News Abyssinian Expedition.[2] He wrote The Mammals of Chile (1943) and co-wrote Artist and Naturalist in Ethiopia (1936).[3] He died a bachelor on 20 June 1947.
Patterson, B.D. (1983). "The journal of Wilfred Osgood: The Marshall Field Chilean Expedition of 1922–23". Field Museum of Natural History Bulletin. 54 (2): 8–11, 28–33.