They feed on till the leaves are falling, and then fix themselves by their claspers to a silken carpet which they construct on a twig. Here they remain, exposed to all the wintry blasts and frosts, till the new leaves are out in the spring, when they again commence feeding, and continue to do so till they are full grown—in May or June.
The under side of this species is shown in [fig. 76], in which will also be observed the eye-like spots of the fore wings which have given rise to its specific name (Iris).
The caterpillar ([Plate VIII], fig. 5) is a very peculiar creature. Its body is green, with seven oblique yellowish stripes on each side, and it has a pair of horns attached to its head.
The chrysalis ([Plate VIII], fig. 10) may be found in June, suspended to the under side of a leaf. It is of an apple-green colour, and still exhibits the oblique stripes which we observed in the caterpillar.
This insect is not to be found in either Scotland or Ireland, but is more or less abundant in many of the oak woods of the midland and southern counties of England. Among the numerous favoured localities, we may mention Colchester, Forest of Dean, Northamptonshire, Ipswich, Huntingdonshire, Buckinghamshire, Epping, Lyndhurst, and the Isle of Wight.