196 BRITISH LEPIDOPTERA. 



ventrally. These hairs are rather bright brown, and extend over 

 the terminal area, where, however, they are mixed with darker 

 ones, with recurved ends, which form a cremastral set of hooks 

 that hold to the pupal silk more firmly than is often found in 

 the Lachneids. The dark hooks' are especially terminal, and may 

 be 50 or 60 in number, but silk and larval hairs make them nearly 

 impossible to count. The wing-margins, which meet in front for about 

 2mm., are about half-way down the pupal length, then forward 

 in the middle line are the 2nd tarsi, the 1st tarsi, the maxillae, and 

 the labial palpi, which are small and short, but well exposed by 

 the narrowness and separation in the middle line of the maxillae. 

 The oral region is very smoothed down. The labium and its palpi 

 have almost a glazed surface, and are paler than the surrounding 

 parts, indicating a very short ancestry for their being so fully 

 exposed, the labrum is above this and the jaws (mandibles) at each 

 side. In some specimens, on the cheek, at each side of the labrum 

 is a prominent point, which is not the mandible. The glazed eye 

 is small and in the usual position, the antennae extend downwards 

 between the 2nd legs and the wings all but as far as the ends of 

 the ] st tarsi. The narrow margin of hindwing extends to the hind 

 margin of the 3rd abdominal segment. On the forewing the neuration 

 is not shown and Poulton's line is absent or extremely close to the 

 actual margin. The abdominal segments have some pits along their 

 median and anterior portions (Chapman). Ochsenheimer describes 

 the pupa as " short and thick, blackish-blue, and here and there 

 red-haired." De Geer writes : " The pupa is bluish-black and drab, 

 length nine and a half lines (it is remarkable that larvae two inches 

 in length transform into pupae hardly half as long) ; it is covered 

 with a reddish-white powder, and is remarkable in that the upper 

 part of the corselet and the head are supplied with many small red 

 hairs ; similar hairs are seen on the abdominal segments, but they 

 are not so numerous." 



Dehiscence. — The pupal dehiscence is by splitting down the 

 dorsal line to end of mesothorax, the separation of the wings from the 

 antennae and from the metathorax, some loosening of antennal base, 

 and separation of prothorax, so that it may even be carried away and 

 lost. 



Foodplants. — Various species of Sdlix ^De Geer), Salix caprea, 

 Vaccinia m myrtillus (Ochsenheimer), Populus tremula (Moeschler), 

 Cylisus fViertlJ, birch and Cory I us mandschurica (Staudinger), 

 Betula alba (Teich), Salix, Populus (Riihb, apple, willow (Stephens). 

 Parasites. — Weaver notes (Zool., xv., p. 5718) the breeding of 

 a large ichneumon from a pupa of this species. The name of the 

 parasite is not mentioned. 



Habits and Habitat. — -When at rest the imago sits with its 

 antennae drawn back, the forewings placed roofwise, the front 

 margin of the hindwingS projecting for some distance beyond the 

 front (costal) margin of the forewings, the hind portion of the 

 wings flattened, until the whole insect appears to be excellently 

 protected by its resemblance to a leaf, the grey thoracic crest and 

 margins of the wings looking just like the dust or bloom on the 

 edge of many dead leaves that have wintered. Both sexes renriin 

 immovable all day, but become restless at dusk, and the female 



