Henrietta Bancroft taught nature study and elementary science at the Walden School in New York.
Richard G. Van Gelder was the chairman of the Mammology Department at the American Museum of Natural History in New York City.
Helen K. Davie has illustrated many books for children, including What Lives in a Shell? by Kathleen Weidner Zoehfeld, and Echoes for the Eye: Poems to Celebrate Patterns in Nature by Barbara Juster Esbensen. Ms. Davie lives in San Jose, CA.