According to Duponchel this species occurred in Normandy, Central and Northern Europe, as far back as 1829. A much paler form inclining to silvery, var. esmeralda, Oberthür, is found in Ussuri, North China, and other parts of East Asia.
The Burnished Brass (Plusia chrysitis).
Two forms of this metallic-looking species are represented (Plate [22]); 5 is typical and 6 shows the ab. juncta, Tutt. Between these are various intermediate stages leading to the complete division of the central band. The broken central band is a character of var. nadeja, Oberthür, from Amurland and
Japan, but that form has also a more or less complete series of ochreous-brown dots on the outer area. The metallic colour is sometimes greenish in all forms.
The caterpillar is pale green, with a darker green line along the middle of the back, bordered on each side by an irregular white line; an oblique white streak on the sides of each ring from 4-11; a stripe low down along the sides is white; head, yellowish tinged. It feeds on stinging nettle, probably on other plants, and after hibernation attains full growth about May. In favourable seasons caterpillars also occur in July and August. The moth is out in June, July, and August, less frequently in September, and may be found flying along the sides of hedges and ditches, especially where flowering weeds are plentiful, throughout the British Isles; so far, however, it has not been recorded from the Hebrides, Orkneys, or Shetlands.
The Scarce Burnished Brass (Plusia chryson).
The more or less square golden (sometimes green-tinged) patch on the velvety purplish brown fore wings, distinguish this species (Plate [24], Fig. 1) from any other British Plusia.
The caterpillar is green, with a darker line along the middle of the back, and a fine white line on each side of it; there is a dark green stripe low down along the sides, edged below with white, and oblique white lines run from it to the central line on rings 3-11. It feeds on hemp-agrimony (Eupatorium cannabinum), hibernates when small, and completes its growth in May or early June.
The moth is out in July and August, and is said to be occasionally seen, on sunny days, flying about, or resting on, the flowers of the hemp-agrimony and other plants. Night, however, is its more usual time of activity, and it may also be found at the blossoms of the larval food plant, and at those of honeysuckle, etc.