The caterpillar is green, with a darker green line along the middle of the back, and a white stripe on each side of it, the inner edge of each of the latter irregular; head, greenish grey, and the bristle-bearing raised dots are shining green with a dusky cap. It feeds on _Brachypodium sylvaticum_, but seems to accommodate itself to a diet of _Phalaris arundinacea_, and would perhaps eat other grasses: August to May. (Plate 23, Fig. 3; after Hofmann.) The moth is out all through the summer months, and {61} frequents marshes, damp rides and borders of woods, heaths, and where there is plenty of tall grass. The species is widely distributed over England and Wales, although it appears to be rather scarce in the midlands and northwards. In Ireland it is generally abundant, but in Scotland it has only been noted from the south, and is there local and rare. The distribution abroad includes Amurland, Corea, and Japan. THE SMALL PURPLE BARRED (_Prothymnia viridaria_). The fore wings of this species (Plate 21, Figs. 10 [male], 11 [female]) range in colour from olive grey to olive brown, and are frequently adorned with two rosy-red (typical) or purplish bands (_aenea_, Haw.). In some specimens the bands are of a dusky hue and not very distinct, whilst in others the wings are of a uniform dingy brown tint (ab. _fusca_, Tutt). The caterpillar (Plate 25, Fig. 2) is velvety-green above and paler beneath, yellowish between the rings, with a dark green slender line bordered by paler lines along the back, and three pale lines along the sides; below the yellowish spiracles there is a broader pale line becoming whitish on rings 9-12; head, green mottled with brown (adapted from Hellins). It is to be found in August and September on the common milkwort (_Polygala vulgaris_). On May 31, 1906, I met with the moth in some numbers on a marshy bit of heath in Surrey, where there was a plentiful growth of lousewort (_Pedicularis_), but, so far as I know, no _Polygala_. All the moths were much below the average size, the bands were mainly purple, but in no case rosy. The moth flies in May and June, and specimens have been captured both earlier and later. Except that it does not appear to occur in the extreme north of Scotland, the species seems to be pretty generally distributed over the British Isles, and is often very common in many parts. The eastern distribution extends to E. Siberia. {62} THE SPOTTED SULPHUR (_Emmelia trabealis_).