The caterpillar is long, slender, and wrinkled, especially on the sides; the ground colour is green, inclining to yellowish; three lines along the back, the central one dark green, and the others yellowish; sometimes a rosy stripe, or a series of dashes along the sides; the points on the last ring are green, or rosy. It feeds, in the autumn and again in the spring after hibernation, on sallow, birch, hawthorn, bilberry, wild strawberry, etc. It will also eat rose, but as the specimens resulting from caterpillars reared on rose are frequently small, such food is probably unsuitable; garden strawberry, on the other hand, is an excellent pabulum. A photograph of the caterpillar by Mr. H. Main is shown on Plate [69], Fig. 1. There is a second brood in late June and in July. The first generation of the moth is out in May and June, and the second emerges in the autumn; specimens, possibly of a third generation, have been seen in December in favourable localities.
The species, which frequents woods and hedgerows, and is pretty generally common, is to be found almost everywhere throughout the British Isles. It has not, however, been noted from Shetland.
The distribution abroad extends to Amurland, China, and Japan.
Dark Marbled Carpet (Cidaria immanata).
This is another exceedingly variable species (Plate [66]), and here again six examples have been chosen to illustrate something of the range of aberration. Figs. 7 and 8 are of the
typical form, and Figs. 9 and 10 show the form marmorata, Haworth (Marbled Carpet); while Figs. 11 and 12 represent specimens from Shetland, and are referable to the island race known as pythonissata, Millière; neither of the specimens figured, however, quite agrees with the type of this form, but Fig. 12 does so fairly well. In some specimens the general colour of the fore wings is tawny or rust-colour, or they are strongly suffused with that tint (ab. ferruginea, Prout). I have such examples in my series of specimens from Lewes and the Shetlands. Ab. thingvallata, Staud., from Iceland, has the fore wings white, with black basal patch and central band, and I have seen at least one example from Yorkshire that closely approached this variety.
The caterpillar is not very unlike that of the last species, but it is rounder in appearance, the general green colour is paler, and the points on the last ring are blunt. It feeds from April to June on sallow, birch, bilberry, and wild strawberry. (Plate [69], Fig. 2, after Hofmann.) The moths are out in July and August, and may be found resting on tree-trunks, rocks, or stone walls; at night, when it is active on the wing, it is said to be often seen in numbers on the flowers of the rush, and this habit has been noted more particularly in Scotland.
The species affects woods and moors, and appears to be found more or less commonly throughout the British Isles.
Marsh Carpet (Cidaria sagittata).
The fore wings of this very distinct species are brown, with white-edged black bands at base and across the central area, the latter with a strong projection on its outer edge, almost reaching a white spot on the outer margin; sub-marginal line whitish, often only traceable on the front edge. The central band is always narrowed below the middle, sometimes divided,