In the _caterpillar_ state also the Purple Emperor is a remarkable creature, of the form shown in Plate I. fig. 5, bright green, striped with yellow on each side, and bearing on his head a pair of horns or tentacles. {116} Though the perfect insect is chiefly found on the oak, the caterpillar feeds generally on the broad-leaved Sallow, though it has been occasionally found on the Poplar. The _chrysalis_, which may be found on the same trees, suspended to the under side of a leaf, is shown at Fig. 22, Plate I. and is of a light green colour. The _butterfly_ appears in July, and is found in oak woods in many localities of the South. The following are a few of these:--Near Colchester, extremely abundant, Epping, Great and Little Stour Woods; Kettering, Barnwell Wold, Northamptonshire; Bourne, Lincoln; Leicester; Reading, Newbury, Berks; Herefordshire; Forest of Dean, Monmouthshire; Warwickshire; Suffolk; Monkswood, Hunts; Clapham Park Wood, Beds; Darenth Wood, Chatham, Tenterden; Ticehurst, Balcombe, Tilgate Forest, Arundel, near Brighton; Lyndhurst; Stowmarket; Isle of Wight. [Illustration: XII.] {117} THE PAINTED LADY. (_Cynthia Cardui._) (Plate VII. fig. 3.) We now come to a very natural group of butterflies, rich, and often gorgeous, in their colouring, and having, both in their perfect and preparatory states, many characteristics in common, in point of habits, as well as of appearance and construction. The caterpillars are all thorny, and the chrysalides are adorned with brilliant metallic (generally _golden_) spots, from which appearance was derived the name "_chrysalis_,"[11] since applied, but somewhat improperly, to the _pupæ_ of _all_ butterflies. This golden effect is produced by a brilliant white membrane underlying the transparent yellow outer skin of the chrysalis, and it may be imitated, as discovered by Lister many years ago, "by putting a small piece of black gall in a strong decoction of nettles; this produces a scum which, when left on cap-paper, will exquisitely gild it, without the application of the real metal." The present species is a highly elegant insect, well named the Painted Lady, and in France the "_Belle Dame_." The colouring of the upper surface is composed of black and very dark brown, with irregular markings of an orange red, tinged partially with a rosy hue. Near the tip of the front wings are several pure white spots. Beneath, the great beauty lies in the delicate pencilling of the hind wing with pearly greys and browns, and contrasted with this, the warm roseate blush and aurora tint on the upper wing. The _caterpillar_ is thorny and brown, with yellow stripes down the back and sides. It feeds on various {118} species of thistle, but sometimes also on the nettle and other plants. The _chrysalis_ is brown and grey, with silver spots.