In her childhood, or caterpillar state, her head is elliptical in shape, of a light pearly color, the rest of the body being a clear bluish-green. A faint yellow band stretches along each side, just below the line of her breathing-organs, from the first to the tenth segment, while the back, between the several body-rings, is crossed by narrow transverse bars, similar in coloration. Each segment, after the fashion of her kith and kin, is adorned with small pearly warts, tinged with purple, some five or six in number, each tipped with a few simple hairs. Three brown spots, bordered above with yellow, ornament the end of the tail. An interesting variety, whose general color is a dull reddish-brown, is sometimes met with, but the lateral and transverse stripes of yellow have disappeared, and the pearl-colored warts with edges of purple have assumed a richer hue and blaze like a coronet of rubies. When at rest, with the rings all bunched and body shortened, the infantile Luna is as thick as a man’s thumb, measuring but two inches in linear direction; but when she sets out upon her travels, feeling the dignity of her station in life, she stretches to her full length of three inches. When have been completed her allotted days of feeding upon the leaves of the hickory, oak, walnut or sweet gum, and she is seriously contemplating the preparing of a shroud and casket in which to await her resurrection-morn, she casts about for leaves, which, when they are found, she securely draws together, and within the hollow space there is soon spun a very close and strong oval cocoon of silk, one and three-fourths inches in length, of chestnut-brown color, thin, and covered with warts and excrescences, but seldom showing the imprints of leaves. Cocoons of Luna so nearly resemble those of polyphemus, that many an experienced collector is greatly chagrined, after getting together a large supply of what he deems Luna cocoons, to find dusky, one-eyed polyphemi to issue from the silken tombs rather than a goodly throng, in delicate bridal attire, of proud empresses of the night. Polyphemus cocoons are, however, somewhat smaller than Lunas, white or dirty-white in color, rounded at each end, and sometimes angular, because of the leaves being unevenly moulded into their surfaces, and generally covered with a whitish meal-like powder. [Illustration: AMERICAN LUNA MOTH. Larva on Branch Below, and Cocoon on Twig Just Above.]