Pretty Watercolor Color Wheel

Hard to argue with the loveliness of a hand-painted color wheel, this one found with amid a stack of old watercolors by an artist unknown, certainly done for a class. Signed on the back by a Lillian Hogan, with a fantastic shadowy leaf pattern that I believe is just toning from something else next to which it was stored for many years.

9" x 9" and in very good condition, watercolor and pencil on a cream watercolor type paper. Based on the pile I found it in, I'd guess 1940s or so.