The expansion of the wings is about 1⅜ inches. The fore-wings are pale greyish-white with numerous small brownish-black streaks, exhibiting a slight concentration near the apex. The hind-wings are dull white, clouded with greyish towards the termen.
This insect is so extremely variable that I have given descriptions of a few of the principal varieties below; all these forms may, however, be connected by specimens exhibiting every intermediate gradation both in colour and in markings.
1. Fore-wings with several large brown spots near the middle.
2. Fore-wings covered with numerous black spots (formerly known as Declana nigrosparsa) (fig. 47).
3. Fore-wings with two more or less conspicuous curved black or brown lines from costa to dorsum (figs. 41, 42, and 44).
4. Fore-wings with these transverse lines joined by two others running parallel to dorsum and costa.
5. Fore-wings with transverse lines and black spots (fig. 43).
6. Fore-wings diffused with dark greyish-black, except two broad bands of the original light colour extending from costa to dorsum; hind-wings darker than usual (fig. 45).
7. Fore-wings with a dark brown central band; hind-wings clouded with dark brown towards termen, with a faint curved transverse line near the middle (figs. 39 and 40).
All these varieties occasionally have tufts of orange-yellow scales on both the wings and on the body, and they also vary in other minor particulars (fig. 46).