The stripe across the wings of this pretty species (Plate [50], Figs. 9 and 10), extending from the apex of the fore wings to near the middle of the inner margin of the hind wings, is normally pinkish red, but it may be of a more crimson or purplish hue; it also varies in width. The fringes are usually pinkish red, and occasionally the margins of the wings are tinged with the same colour. The whitish-ochreous ground colour is normally finely powdered with grey, but sometimes so thickly that a greyish tinge is imparted to the wings. Barrett mentions a specimen with pale smoky brown wings, and, excepting that the tips of the fringes are tinged with pink, the usual markings are absent. In another example, "the space between the central and second lines is filled up with purple brown."
The caterpillar is brownish grey, with three whitish lines on the back, the central one intersecting a series of four dark
lozenges. It feeds on various low-growing plants, such as persicaria, orach, sorrel, etc., but dock seems to be the most frequently selected pabulum. July to May, sometimes feeding up and appearing as a second generation of the moth in August.
Weedy ditches, hedge banks, or moist waste places, are the favourite resorts of the moth; and when one example is flushed from its lurking place, others are almost certain to be hiding in the immediate vicinity.
Widely distributed throughout England, but most common in the south; found also in North and South Wales; and sparingly in Scotland to Aberdeenshire, also recorded from Arran. Apparently rare in Ireland, as it is only noted from Kerry and Galway.
False Mocha (Ephyra porata).
The wings are pale ochreous brown, finely flecked with purplish grey, and more or less tinged with reddish; the cross lines are indicated by blackish dots, the central shade is greyish inclining to reddish, and the rings enclosing white dots are blackish or dark brown, but sometimes indistinct on the fore wings; occasionally there are some purplish grey clouds on the outer marginal area, and this is more frequent in examples of a second generation. Sometimes the wings are entirely suffused with dull reddish brown, and all the markings, except the white dot on the hind wings, are obscured. (Plate [53], Figs. 7 and 8.)
The caterpillar is pale pinkish ochreous, with inconspicuous wavy white lines, and brownish dots, on the back; dark oblique marks on the sides; the head is pencilled with darker brown. It feeds on oak and birch in June and July, and individuals of a second brood sometimes occur in September or October.
The moth is out in May and June, and rests in the daytime
among the foliage of trees and bushes in or around woods. Like others of the genus, it is attracted by light, and is said to visit the sugar patch. Specimens of a second generation sometimes appear in August and September, but, I believe, more frequently in the breeding cage than in the open. Although it has been recorded from several of the northern counties from Staffordshire to Cumberland, this is more especially an inhabitant of the south and west of England, and of Wales. In Scotland, it is known to occur singly and rarely in Clydesdale and Arran, and has been found in Perthshire.