Affiliations Research 1920AssistantCarnegie Institution1922AssistantCarnegie Institution1923Research AssistantCarnegie Institution1924Research AssistantCarnegie Institution Of Washington1926Research AssistantCarnegie Institution Of Washington1927Research AssistantCarnegie Institution Of Washington 1920Zoology[role unknown]1922Zoology[role unknown]1923Zoology[role unknown]1924Zoology[role unknown]1926Zoology[role unknown]1927[subject unknown][role unknown]