Pl. 59. 1, 2. FOX MOTH, _males_; 3 _female_.
{ 123} The late Mr. Robson used to collect the caterpillars on fine days in early spring, put each caterpillar into a separate paper box about two inches square, and keep them on a shelf over the kitchen fire, where they would duly pupate. Various methods for keeping these caterpillars through the winter have been described, and all appear to have been fairly successful. The most simple would seem to be the following: Bore a number of holes in the bottom of a roomy box, and fasten wire gauze on a close fitting frame to serve as a top. Cut a tuft or two of heather to cover the floor space of the box. Caterpillars collected in the autumn may be put into this receptacle and supplied with food, such as bramble or sallow, as long as they seem inclined to feed. Do not crowd too many into the box, and let it stand out in the garden, preferably on the soil.
The moths emerge in May or June. The males are very active on the wing in the afternoon sunshine, and later on, and may often be seen in numbers dashing hither and thither in an apparently erratic flight over heaths and open spaces, in search of the females. The latter do not fly till night, and occasionally they are attracted to a bright light.
Except that it has not been noted in the Shetlands, the species occurs throughout the British Isles. Abroad its range extends over Europe, and it is found in Amurland.
The male is reddish brown, more or less clouded on the forewings with ochreous; and the female is yellow, or whitish ochreous. Sometimes this colour distinction of the sexes is reversed, and the males are pale whilst the females are dark. In the fens of Cambridgeshire notably, pale or yellowish males are not altogether uncommon. Such specimens would seem to accord better with the Linnean type than the more usual form indicated above. Barrett mentions, among other aberrations, male specimens from South Wales with the whole of the fore and hind wings deep rich glossy purplish chocolate. { 124}
There is variation in the two whitish or silvery marks on the fore wings, the upper one is often very small, sometimes quite absent, and the lower one reduced to a crescent. The chocolate brown cross lines, of which there are usually two on the fore wings, are sometimes faint or entirely missing. Tutt has recently named nine forms, chiefly colour aberrations, and two others were previously named. (The moth is figured on Plate 61, and the early stages on Plate 60.)