In the name—­Eacles Imperialis—­there is no meaning or appropriateness to “Eacles”; “Imperialis”—­of course, translates imperial—­which seems most fitting, for the moth is close the size of Cecropia, and of truly royal beauty.  We called it the Yellow Emperor.  Her Imperial Golden Majesty had a wing sweep of six and a quarter inches.  From the shoulders spreading in an irregular patch over front and back wings, most on the front, were markings of heliotrope, quite dark in colour:  Near the costa of the front wings were two almost circular dots of slightly paler heliotrope, the one nearest the edge about half the size of the other.  On the back wings, halfway from each edge, and half an inch from the marking at the base, was one round spot of the same colour.  Beginning at the apex of the front pair, and running to half an inch from the lower edge, was a band of escalloped heliotrope.  On the back pair this band began half an inch from the edge and ran straight across, so that at the outer curve of the wing it was an inch higher.  The front wing surface and the space above this marking on the back were liberally sprinkled with little oblong touches of heliotrope; but from the curved line to the bases of the back pair, the colouring was pure canary yellow.

The top of the head was covered with long, silken hairs of heliotrope, then a band of yellow; the upper abdomen was strongly shaded with heliotrope almost to the extreme tip.  The lower sides of the wings were yellow at the base, the spots showing through, but not the bands, and only the faintest touches of the mottling.  The thorax and abdomen were yellow, and the legs heliotrope.  The antennae were heliotrope, fine, threadlike, and closely pressed to the head.  The eyes were smaller than those of Cecropia, and very close together.

Compared with Cecropia these moths were very easy to paint.  Their markings were elaborate, but they could be followed accurately, and the ground work of colour was warm cowslip yellow.  The only difficulty was to make the almost threadlike antennae show, and to blend the faint touches of heliotrope on the upper wings with the yellow.

The eggs on the floor and curtains were guarded with care.  They were dotted around promiscuously, and at first were clear and of amber colour, but as the little caterpillars grew in them, they showed a red line three fourths of the way around the rim, and became slightly depressed in the middle.  The young emerged in thirteen days.  They were nearly half an inch long, and were yellow with black lines.  They began the task of eating until they reached the pupa state, by turning on their shells and devouring all of them to the glue by which they were fastened.

They were given their choice of oak, alder, sumac, elm, cherry, and hickory.  The majority of them seemed to prefer the hickory.  They moulted on the fifth day for the first time, and changed to a brown colour.  Every five or six days they repeated the process, growing larger and of stronger colour with each moult, and developing a covering of long white hairs.  Part of these moulted four times, others five.