FIREFLY. The name of many luminous beetles of the families Lampyrithe and Elaterithe, the former of which is known as the fire fly or lightning-hug family. The Lampyrid:e are pentamerous beetles of small size and soft texture, with the bead frequently hidden under the prof horax, but sometimes prominent and with serrate antenna: the elytra are soft and :yielding. are often abbreviated, and in sonic genera totally wanting in the females, which are wingless. and larv:e-like in other respects. These and the true larva' are called glowworms. and are often more luminous than the adult male lightning-bugs. "The are flattened, often dark-colored and velvety, and have an oeellus on each side of the retractile head; they are generally carnivorous, living under stones and bark, and upon the ground, where they devour snails and lame of insects. Sometimes the velvety larvae of certain species of Telephorus wander about upon the snow, giving rise to stories of showers of worms." The family Lampyrithe is confined to warm or tropical lands, and is very abundant in southern Europe and in most parts of the United States. Fireflies are gregarious, and their luminosity is most evident on warm, dark nights. The light giving part is situated ordinarily on the sides of the abdomen, and the light is greenish-white, like phosphorescence; but in South America there is a remarkable form, probably a female of the group Phengodini, which flashes a red light at each end of the body and a green light along the sides, sug gesting signals, so that it is known in Paraguay as the railway beetle. The emission of light by
the lampyrid lightning-bugs and glowworms is intermittent, but at definite intervals, in one case averaging about thirty-six flashes a minute, but this varies a little from night to night, per haps with the temperature. The function of the light of Lampyrithe is unknown to us, but since many of the fireflies have unusually well-devel oped eyes, and since most of them are active at night, the flash would seem in some way to be important for the firefly. In some forms (as Pyropho•us) not only both sexes, but the eggs, larvae, and pure are luminous. A common species of lampyrid firefly in the eastern United States is Photuris Pennsylranica, about half an inch long, yellowish and obscurely striped; its luminous larva has a brush-like anal leg. A Western species is Photuris pyralis, which has brownish-black elytra margined with dull yellow, and whose larva live in the ground and feed upon worms. The most familiar European species is the common glowworm of England (Lampyris 2? ortiluca), of which the blackish female, half an inch in length, is entirely wingless and without elytra, and crawls about in the grass emitting a soft, steady light, occasionally interrupted. The males and the larva' are also faintly luminous, the latter being noted for their voracity and their devouring of snails. In another genus, plentiful in southern Europe, both males and females are winged and luminous, the male giving a stronger light than the female.