The figure Genius in English literature has received attention from scholars from the eighteenth century to the present day, especially with reference to Spenser, Jonson, and Milton. Perhaps the most comprehensive treatment of the subject is that by Professor E. C. Knowlton, in a series of articles in the 1920s, tracing the appearance and literary use of the figure from antiquity, through the middle ages, to the end of the sixteenth century. As the substance of much of Knowlton's investigation is in his study of 'The Genii of Spenser' (1928), this article merits a statement of the author's purpose and procedure.