and edged above the inner margin by a dark chocolate brown curved line; raised scales on the central area and on the cross lines. Two oval reddish brown marks on the front of the collar have some resemblance to a pair of spectacles, hence the English name. (Plate [22], Fig. 2.)
The caterpillar is green, sprinkled with white dots; on rings 4, 5, and 11 are whitish-edged darker marks, and there is a dark line, also whitish-edged, along the middle of the back between rings 5 and 11; a white line on the back from ring 4 to the brownish head, and white-edged dark oblique lines on the sides of rings 6 to 11; the line low down along the sides is whitish with an ochreous tinge. A purplish brown form also occurs (Plate [27], Fig. 2), in which the pale markings are ochreous tinged. It is found from July to September on nettle and hops, the latter more especially. The earlier caterpillars, in some years, attain the moth state in August or early September, but the bulk of them remain in the chrysalis state during the winter, the moth emerging in June or July of the following year.
The species is not uncommon in most southern English counties, but becomes less frequent or more local northwards from the Midlands to Cumberland, Northumberland, and South Scotland. It occurs in Wales, and is widely spread in Ireland.
The range abroad extends to Amurland.
The Spectacle (Abrostola tripartita).
This species, known also as urticæ, Hübner, has the basal and outer marginal areas of the fore wings whitish grey, finely mottled with darker grey; the central area is greyish brown, mottled with darker brown. The spectacle mark in front of the thorax is whitish grey, ringed with black, and the raised scales on the cross lines and central area of the fore wings are more distinct in this species (Plate [22], Fig. 3). The
caterpillar is pale green, with white-edged dark-green
-shaped marks along the back, most in evidence on rings 4-11; two slender whitish lines on each side, only distinct on rings 1-4; a white stripe low down along the sides, edged above with dark green and with whitish streaks from it to the white edging of the marks on the back. Head, green, rather shining, with dusky marks on each cheek (adapted from Fenn). It feeds in July, at night, on the common stinging nettle, from the foliage of which it may be beaten out, or, by searching, found on the undersides of the leaves. In some years there is a second brood in September.
The moth is out in June, sometimes late May, and, when there is a second emergence, in August. Occasionally it is seen on fences, etc., but at night it visits the blossoms of various plants, both wild and cultivated; the flowers of spur-valerian (Centranthus ruber), honeysuckle, and woundwort (Stachys) being especially attractive, as also they are to the Dark Spectacle, and most of the species of Plusia.