The caterpillar is green, sometimes tinged with olive and freckled with darker green; there are three dark-edged pale-green lines along the back; the under surface is tinged with yellowish, and is separated from the green colour of the upper surface by a whitish stripe, edged above with black; head, brownish, with darker freckles. It occurs in April and May, when it feeds on bramble, rose, oak, sallow, and some low-growing plants.
The moth is found in September and October throughout England, and Scotland up to Moray.
The Orange Sallow (Cirrhia (Xanthia) citrago).
The ground colour of the fore wings is generally yellow, but in some districts the specimens exhibit a tendency towards orange-red. The latter tint is very decided in var. aurantiago, Tutt. There is but little variation in marking, but the central cross line is broader in some specimens than in others. (Plate [10], Fig. 1.)
The caterpillar is dark olive-grey above, with white dots, and obscure greenish beneath; of the three whitish lines along the back, the central one is rather wider than the other two, which are edged above with black; along the region of the spiracles the colour is whitish grey. Head, brown, shining, and darker on the mouth; a black mark on ring of body next the head. (Adapted from Porritt.) It feeds on lime (Tilia vulgaris) in April and May, and conceals itself between two spun-together leaves during the daytime. In such retreats I have frequently detected them by simply standing under the branches and looking upwards and outwards from the trunk. When nearly full grown they more often descend the tree, and hide by day
among the undergrowth, etc., at the base of the trunk, whence they return to their feeding quarters by crawling up the tree at dusk.
The moth is out in August and September, and although it does not seem to care much about the collector's sugar when spread on tree trunks in the usual way, it seems to accept it freely enough when daubed on the foliage. The leaves of the lime are, however, generally well coated with a sweet substance proceeding from Aphides, and commonly known as honeydew. This in itself is very attractive to the moths. The species seems to be widely distributed over England, and will perhaps be found in most districts where limes flourish. In Wales it has occurred in Flintshire, Denbighshire, and Carnarvon. McArthur obtained a specimen in the Isle of Lewis in 1887, and Renton records it as found in Roxburghshire. Little is known of it from Ireland, but it has been noted from Wicklow and Galway.
The Barred Sallow (Ochria (Xanthia) aurago).
The ground colour of the fore wings, which in the type is pale yellow, ranges through various shades of yellow to deep orange. The basal and outer marginal bands are pale purplish, in the type, but in the more orange forms the bands are rather more reddish purple. In ab. fucata, Esper, the purplish colour of the bands spreads over the orange central area, and in ab. unicolor, Tutt, the orange invades the basal and outer marginal regions, so that the bands are pretty well obliterated, and the fore wings assume a more or less uniform orange coloration. The latter form is uncommon, but a rarer one in this country is ab. lutea, Tutt, which has the fore wings almost entirely orange-yellow. (Plate [10], Figs. 2 and 3, the latter inclining to ab. unicolor.)
The caterpillar is reddish brown with pale dots, and with