The fore wings of the male of this species are brown, with a bent whitish streak, sometimes broken, passing from the base to the middle of the inner margin, and then to the apex. The hind wings
are smoke coloured, with a light brownish fringe. The female is much less distinctly marked, and presents a rather dingy appearance.
The larva is dingy white, with brown horny plates on the second, third and fourth segments. It feeds on the roots of dead nettles (Lamium album and L. purpureum), black horehound (Ballota nigra), and various other herbaceous plants, throughout the winter months, and is full grown in April.
This insect is abundant everywhere in waste places, and may be seen on the wing in May and June.
Family—Cossidæ
The members of this family have longer antennæ than the Hepialidæ, and the females are provided with extended ovipositors which enable them to place their eggs in the deep crevices of the bark of trees.
The larvæ are naked or only very slightly hairy, and have a plate on the second segment. They feed on the wood of trees or the interior of the stems of reeds. The pupæ have spiny projections on each segment.