_Peacock Butterfly, vanessa Io._—This is considered as one of the most beautiful of European insects, in form and coloring; black, and reddish brown, marked with eyelets of yellow and blue, being its usual tints. The caterpillars are produced from eggs laid on the leaves of nettles; they are black and spiny. They live in company, providing themselves with a common tent or web, where they seek shelter during the night, and from the rains, to which they are very sensitive. The peacock butterfly is found throughout Europe, but is rare in England. The reader is probably aware that Linnæus gave to the butterfly family, in its largest sense, the name of Lepidoptera, or scalywings, from the minute scales, resembling dust to the naked eye, with which their wings are covered. Diminutive as these scales are, they are yet perfect in their order and formation, when examined by a microscope. The wing of a peacock butterfly was submitted to this scrutiny, and the scales actually counted by a patient observer; a quarter of an inch square was cut from the wing and placed under the instrument, when seventy rows of scales were counted on it, ninety to each row, so that a single square inch must contain 100,936 of these minute scales! The peacock butterfly is unknown in America. NOTE BB. THE GLOW-WORM, (_lampyris noctiluca_) p. 206. “Our English glow-worm, as we presume most people are aware, is the wingless female of a winged beetle, which also carries a light, though one of much inferior lustre.” “It is supposed by some, that the light of the wingless beetle is bestowed for her protection, to scare away her hungry foes, the nightingale and other birds of night; it is opined by others, that the insect’s gift of brilliancy, like many of the like bestowed upon mankind, is the very means of her destruction, the very lure and light by which her biped foes are assisted to discover and devour her.” So writes the author of Acheta Domestica when speaking of the glow-worm of England. This little creature is farther described as having “a tiny head,” “a slate-colored, oblong, flat, and wingless body, all divided into rings, and bearing at its nether extremity, the _lamp_—by night, a lustrous emerald, by day, a dull pale spot, composed of the sulphur-colored substance which supplies the light.”