The caterpillar feeds in September, and again in May, after hybernation, on several of our forest trees, including the oak (Quercus Robur), elm (Ulmus campestris), birch (Betula alba), and beech (Fagus sylvatica). It is of a dingy olive colour, with a dark dorsal line, on each side of which is a row of white spots; and it has three pairs of claspers.
The Scalloped Oak (Crocallis elinguaria)
This species is common and widely distributed, and may be seen flying at dusk towards the end of July and throughout August. It is represented in fig. 4 of [Plate XII]. The antennæ of the male are strongly pectinated; those of the female are simple.
The caterpillar may be found in the autumn, and again in spring, feeding on the honeysuckle (Lonicera Periclymenum), whitethorn (Cratægus oxyacantha), blackthorn (Prunus spinosa), beech (Fagus sylvatica), and various fruit trees. It is full grown in June, when it turns to a chrysalis in a cocoon spun between leaves or moss on or near the ground. It is of a greyish-brown or greyish-purple colour, and looks very like a piece of twig.
The August Thorn (Eugonia quercinaria)
Our last example of this family is the August Thorn, represented in the accompanying woodcut. The fore wings are ochreous yellow, crossed by two nearly parallel lines of dark brown. In order to distinguish between this and one or two similar species it must be observed that both these lines are angulated near the costa, the inner one very sharply so; and between the two is a distinct brown spot near the costal margin. The hind wings are paler, and are crossed by an indistinct darker line. The antennæ of the male are strongly fringed; those of the female are simple.
The moth is very common in August and September, and is readily attracted by lights in the evening.