In the early 1880s, biologist Henry Fairfield Osborn conducted some of the first questionnaire research in American psychology. This article details how he came to distribute Francis Galton's questionnaire on mental imagery in the United States, as well as how he altered it to suit his own burgeoning psychological research interests. The development and circulation of questionnaires at the very beginning of American scientific psychology, first by Osborn and later by G. Stanley Hall, is discussed in terms of the new psychology's often-overlooked methodological plurality. Further, Osborn's late nineteenth century interest in individual variation and group differences in mental imagery ability are discussed in relation to his pervasive educational and social concerns, as well as his eventual status as a prominent eugenicist in the twentieth century United States. This research into mental imagery ability foreshadows the eugenic-oriented intelligence testing that developed in the early twentieth century.