Volume Ii Part 17 (1/2)
Two forms of this pretty little species (known also as _auroraria_) are shown on Plate 45. Fig. 1 represents the more usual form, but between this and the almost entirely purple variety (Fig. 4), which occurs chiefly in the north, there are various modifications. Then again, especially in the south of England, there is a tendency to become entirely yellow, the purple, inclining to crimson in such specimens, being confined to the front margin and cross lines on the fore wings, and a narrow band on the outer margin of all the wings.
The caterpillar is pale brownish, inclining to ochreous at each end, marked with irregular blackish lines on the back, and dots and streaks on the sides. Its natural food plant seems to be unknown, but when reared from the egg the caterpillar will eat knotgra.s.s, and sometimes a few will feed up and attain the moth state the same year. August to May.
The moth occurs in late June and in July, and frequents fens, boggy heaths, and mosses. Although odd specimens may, occasionally, be flushed during the day, the collector will need to be up early in the morning if he would see this species on the wing, as it seems to fly most freely about sunrise. The New Forest in Hamps.h.i.+re is a noted district for it, as also are Ranworth, Horning, etc., in Norfolk, and Witherslack in Westmoreland. In Ireland, it is found in counties Galway, Kerry, and Mayo.
Abroad, the range extends to Amurland, China, Corea, and j.a.pan.
WEAVER'S WAVE (_Acidalia_ (_Ptychopoda_) _contiguaria_).
The earliest known British specimen of this species (Plate 45, Figs. 2 and 5) was taken in North Wales by Weaver, in 1855, {110} and was figured and described in _The Entomologist's Annual_ for 1856 as _Dosithea eburnata_, Wocke. About seven years later Greening captured a female specimen, and he subsequently reared the insect, when it became known as ”Greening's Pug.”
Still later, about 1875, the English name was changed to ”Capper's Acidalia.”
Fortunately, the species seems not difficult to rear from the egg, otherwise specimens in collections would be not only very limited in number, but frequently very indifferent in condition.
In colour the moth is whity brown, more or less dusted or clouded with dark grey; except in the darker forms, three irregular black lines on the fore wings, and two on the hind wings, are clearly seen. It flies at dusk in June and July, and sits by day on lichen-covered rocks.
The caterpillar is pale ochreous brown, with irregular dark brown lines. It feeds on ling (_Calluna_) and crowberry (_Empetrum_) from September to May; but when eggs are obtained, the caterpillar hatching from them may be kept on chickweed, knotgra.s.s, etc., and the moth be reared the same year.
Mr. R. Tait records the finding of ten caterpillars on navelwort (_Cotyledon_) growing among heather in a very sheltered corner among rocks in North Wales, at Easter, 1906. He also notes that moths reared in captivity pair readily.
The British localities, all in North Wales, are Aber, Bangor, Barmouth, Bettws-y-coed, Conway, Dolgelly, Lanfairfechan, and Penmaenmawr.
THE LEAST CARPET (_Acidalia_ (_Ptychopoda_) _rusticata_).
The whitish fore wings of this species (Plate 45, Figs. 3 and 6) are crossed by a blackish central band, and there is a blackish patch at the base of the wings, with an extension along the front margin, almost or quite to the central band; the hind wings have a central dot, and three or four dark grey wavy lines, the s.p.a.ce between the first and second darkened, and appearing to be a continuation of the fore wing band. The thick set, pale ochreous-brown, or grey-brown, caterpillar (Plate 48, Fig. 1, drawn from a skin) has three more or less distinct pale lines along the back, and a series of darker diamonds along the central area; head, brown. In the open, its food probably consists of decaying or withered leaves, but when treated in captivity it will eat and thrive upon growing knotgra.s.s, groundsel, dandelion, etc. August to May. Mr. Mera mentions that some caterpillars he reared on dandelion produced moths that were larger in size than most captured specimens.
[Ill.u.s.tration]
2 Pl. 44.
1. SMALL GRa.s.s EMERALD: _caterpillar_.
2. LITTLE EMERALD: _caterpillar_.
3, 3a. SMALL EMERALD: _caterpillar, chrysalis and coc.o.o.n_.
[Ill.u.s.tration]
2 Pl. 45.
1, 4. PURPLE BORDERED GOLD.
2, 5. WEAVER'S WAVE.
3, 6. LEAST CARPET.
7, 10. RUSTY WAVE.
8, 11, 14. SMALL DUSTY WAVE.
9, 12. DOTTED BORDER WAVE.
13. SILKY WAVE.
15, 18. DWARF CREAM WAVE.
16. ISLE OF WIGHT WAVE.
17. SATIN WAVE.