In this species the ground colour of the fore wings varies from whity brown to ochreous brown with a slight reddish tinge. A greyish shade spreads from the base along the median vein to below the reniform stigma in the paler and more typical specimens; the inner area is dark brown, but widely broken below the reniform by the grey suffusion. The specimens figured on Plate [14] (Figs. 1 ♂, 2 ♀) are from Sligo, Ireland, and are referable to var. brunnea, Tutt. The inner area in this form is red-brown, or inclining to blackish brown.
The caterpillar is green, with three yellow lines along the back, and a reddish orange stripe along the area of the spiracles; a series of black-circled white dots on each side of the central line; in the form figured (from a skin) on Plate [8], Fig. 3, the lines on the back are white, and the spaces between them black, dotted with white; the stripe along the reddish spiracles also white, edged above with black; head, shining light reddish brown. It feeds, from May to July, on various low herbage, such as dock, persicaria, knotgrass, etc., also sedges and yellow flag.
The moth appears in September and October, and again in March and April, but seems to have been noted at various times both earlier and later. Mathew records that a female captured at sugar on June 11, deposited 36 eggs during the following week. These were laid in a chip box, and the caterpillars hatched out on June 24, fed up quickly on knotgrass, attained full growth by July 24, and pupated about that date.
One moth emerged September 29, and five others, including three cripples, later.
This species is most frequent in Ireland and Scotland, being distributed throughout the latter country to Orkney and Shetland. It has been noted from almost every part of England, but does not seem to be plentiful generally in the country.
The distribution abroad ranges to East Siberia and to North America.
The Mullein (Cucullia verbasci).
Two specimens, representing both sexes, of this species are shown on Plate [15], Figs. 1 ♂, 2 ♀. Sometimes the darker colour on the marginal areas, especially the inner, inclines to blackish; while in some specimens the whole of the fore wings is suffused with brownish.
The caterpillar is white with a greenish tinge, each ring of the body is banded with yellow, has four black spots on the back, and some black dots and lines on the sides; the head is yellowish, dotted with black. It may be found in June and July quite exposed on mullein (Verbascum thapsus, and V. pulverulentum); also figwort (Scrophularia nodosa, and S. aquatica). Barrett states that it has been noted on Buddlæa globosa, an American plant sometimes grown in gardens. These caterpillars are certainly attacked by parasitical flies, but do not seem to be quite so frequently "stung" as those of some other species of the "Sharks." The caterpillar figured on Plate [18], Fig. 1, was obtained at Box Hill by Mr. Norman Riley.
The moth is out in late April and in May, and, except an occasional capture at light, is rarely seen in the open. The caterpillars are probably obtainable in most English and Welsh counties, especially the southern ones of both countries, wherever there is an abundance of its food plants. Except that McArthur found the species in the Isle of Lewis, in 1901, there is no record from Scotland. In Ireland it has been recorded from Dublin by Birchall; and in 1901 three moths were taken at Timoleague, Co. Cork, and caterpillars later on were plentiful in the district.