The egg is of a dull creamy tint, ribbed, and with a slight depression on the top. The eggs were laid early in August, on blades and stems of a kind of grass; also on the leno covering, and the sides of the glass jar in which the female butterfly was enclosed. The caterpillar when full grown "is drab, delicately mottled, with longitudinal stripes broadest along the middle segments, viz. a dorsal stripe of olive-brown, very dark at the beginning of each segment, with a thin edging of brownish-white. Along the subdorsal region are three stripes, of which the first is composed of a double narrow line of yellowish-brown, the second wider of the mottled ground colour, edged with paler above and with white below; the third of similar width is of a dark grey-brown, edged above with black. The spiracular stripe is broader and of nearly equal width, pale ochreous-brown, edged with brownish-white both above and below; the spiracles are black. The head is brown, and the principal stripes of the body are delicately marked with darker brown" (Buckler). The chrysalis is described as "obtuse, rounded, tumid, and smooth, the abdominal rings scarcely visible, and wholly of a deep red mahogany colour." It was "in a hollow space a quarter of an inch below the surface, the particles of sand and earth very slightly cohering together, and close to the roots of the grass, yet free from them." The figures of caterpillar and chrysalis are drawn from those in Buckler's "Larvæ of British Butterflies." [Illustration: _Pl._ 78. =Grayling Butterfly.= _Males_, 1, 3 _(Chalk)_, 2 _(Heath); females_, 4 _(Heath)_; 5, 6 _(Chalk)_.] [Illustration: _Pl._ 79. =Grayling Butterfly.= _Egg enlarged; caterpillar and chrysalis (both after Buckler)._] The caterpillars hatch in August, hibernate when quite small, and feed up in the spring and early summer. They live upon grasses, such as _Triticum repens_, _Aira cæspitosa_, and _A. præcox_. The butterfly delights in sitting rather than flying about cliffs and sand-hills, heaths and downs, stony hillsides, dry fields, and even open woodlands. It is fond of sunning itself on rocks, and by some of the old Aurelians it was called the "Rock Underwing," no doubt in reference to the pattern and colour of the under side. It was also known as the "Tunbridge Grayling" some two hundred years ago, when it was said to be "very rare about London." It has long since been ascertained to occur in almost every county in England and Wales, as far north as Sutherlandshire in Scotland, and is widely distributed in Ireland.