Ater several seasons of collecting, it has become evident that Gluphisia lintneri Grote and G. avimacula Hudson, which both occur at Ithaca, are not forms of the same species, as they do not fly at the same time, lintneri being on the wing about a month before avimacula, the former occurring in late April and the latter in late May, and this lapse of time between the two periods of flight of the forms does not constitute enough for the production of two broods.