 Pollination was studied further by Federico Delpino who coined various terms for the modes and means by which it occurred.Important modern successors like Paul Knuth, Fritz Knoll and Hans Kugler were inspired by Sprengel and brought great advances to the field of pollination ecology and floral biology.After the second World War, their work was continued by Stefan Vogel, Knut Faegri, Leendert van der Pijl, Amots Dafni, G. Ledyard Stebbins as well as Herbert Baker and Irene Baker.