The caterpillar is usually some shade of green, with yellowish lines on the back, and some have brownish marks on the sides; in others there are dark brown marks on the back of each ring. It feeds on the leaves of oak, in April and May.
The moth rests on tree-trunks, fences, etc., and the males may be thus found during the day in February, earlier or later in some seasons; the female is less often obtained on trees and fences, but may be beaten, together with the male, from the dead leaves which remain upon oak and other bushes.
The species appears to occur, more or less locally, in most of the English counties; it has also been recorded from Pembrokeshire and Flintshire, in Wales. In Scotland, it is obtained in
the south, and northwards to Aberdeenshire. There are but two records from Ireland, and these are doubtful.
Abroad, the range extends to Amurland and Japan.
Scarce Umber (Hybernia aurantiaria).
One specimen of each sex of this orange yellow species will be found on Plate [120], where Fig. 7 represents the male, and Fig. 9 the female; the cross lines, in the male, are usually distinct on all the wings, but those on the hind pair are sometimes very faint, and occasionally absent. The ground colour is paler in some specimens than in others, and there is variation in the amount of purplish speckling, in the purplish clouding following the second line, and in the submarginal series of purplish marks of the fore wings. The marginal dots are sometimes absent from the hind wings, most frequently in specimens with faint cross lines on these wings.
The eggs (Plate [125], Fig. 2), when I received them in February, were purplish, or violet brown.
The caterpillar is yellowish, inclining to ochreous, lined with brown on the back, and striped with purplish on the sides; underside, dark purplish brown, inclining to blackish, and striped with yellowish. It feeds in the spring, sometimes to June, on oak, birch, blackthorn, etc., and may be found on the leaves during the day. The moth is out in the latter part of the year, from October, and is best obtained at night, when sitting on the twigs of trees and bushes, but a specimen or two may be found on tree-trunks, palings, etc., in the daytime.
The species is widely distributed over England, and in some parts it is common in woods; also occurs in Wales. In Scotland it is very rare and local in Roxburghshire; local and uncommon in the Clyde area, and has been recorded from other parts of the country up to Aberdeen. Rare in Ireland, but noted from