Lepidoptera The Purple Emperor Butterfly – Apatura Iris
This grand insect is the only British member of its family, and richly deserves its popular title. The male, which is figured on 
Plate V (fig. 1), exhibits a most gorgeous imperial purple, which is reflected at certain angles only from the upper surface of his large and powerful wings. His flight is lofty and vigorous, and among the topmost branches of majestic oaks, where he defies the efforts of would-be capturers. Unlike our other butterflies, he is also a very quarrelsome creature, and will not hesitate to fiercely attack a brother Emperor who dares approach the branch he has selected for his throne.
Many attempts have been made to capture this prized creature by means of a large net mounted on the end of a pole twenty or thirty feet in length, but the wielding of such a cumbersome implement against so powerful an insect is no mean task, and but few fall a prey to such a snare. But it so happens that this imperial personage has a very depraved appetite, the indulgence in which has often brought him to ruin. Instead of searching out the sweets so bounteously supplied by the blossoms that are so attractive to other lepidopterous insects, he delights in sipping the waters of the filthiest puddles, and imbibing the odoriferous moisture of dung and the decomposing carcases of animals. So deeply seated is this depravity of taste that the Emperor may be netted with ease while indulging in his sumptuous feast, and is even to be taken at times with the fingers.
The knowledge of this peculiarity of the imperial palate has led entomologists to abandon the awkward net, and to bait the woods with viands that alone can entice his highness from his lofty seat; and many a splendid specimen has been easily captured while enjoying the luxurious juice of a dead cat, stoat, or rabbit, or of a seething mass of pig’s dung.
The female is larger than her mate, and does not display the beautiful purple reflections that adorn the male. She is very different, too, in her habits, for she sits nearly all day on high branches of trees, giving her attention to the graver duties of an imperial mother, and is consequently but seldom seem. She lays her eggs in July on the sallow (Salix Caprea) or the poplar (Populus), and in less than a fortnight the young caterpillars are hatched. 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.
Fig. 76.-The Purple Emperor-Under Side.
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.