Northern Prairie Wildlife Research Center
Reddish gray with numerous fine wavy black lines; first 2 pairs of prolegs reduced. Head light, mottled, often with 2 thin dark lines extending back from antenna. Abdominal venter pale with purple spots between legs and purplish line on seventh, eighth, and ninth segments. Food: especially maples. Caterpillar: June to November; 2 or more generations in South, 2 in North.