EGG—Conoidal, depressed at top, flat at base, shaped generally like the eggs of Argynnis ( Idalia, Cybele, &c.), but taller in proportion to its breadth than in the species named, with the sides less rounded ; marked by about 20 prominent, vertical, straight ribs, half of which extend from base to summit, forming around the depression a serrated rim, the rest ending irregularly at two fifths to four fifths the distance from base, the shorter ones occasionally joining the others ; marked horizontally by numerous prominent stræ. Duration of this stage from 5 to 12 days, according to the season.