Firefly Flashes

"By what process do fireflies produce the beantiful flashes of light?" That is a qnestion frequently asked, and as entomological books fail to give a satisfactory reply the following explanation may be interesting: I have made a special study of the light, and carefully examined thernechanism of the illuminating segrnents in both male and female specimens. The light emitted, when tested by the spectroscope, gives a brilliant spectrum, which is continuous through all the colors from the red to tho violet rays. The illurninating organs consist of distinct spherical cells, each one of which is about 1.2000 of an inch in diameter, and the beetle has power to illuminate one or manyof these cells at will, prodncing light of corresponding intensity. The cells contain a fluid saturated with phosphorus, and the covering of the cell is so thin that atmosphere coming in contact with it may affect the contents. It has been suggested that the beetle produces the flashes of light or rendera the phosphorus suddenly luminous by electricity - by tbe iujection of warm fluids - or by friction. But it is certain that the flash of light is made in another way. We mayclearly trace a connection between the spiracles and trachea (spiral air tubes) of the beetle and each of the illuminating cells, and find that the little creature renders the phosphorcs contained in the cells luminous by forcing air upon them. The cells when thus excited emit light from their surf ace. We may imitate the act of the beetle by dissecting one and placing the illuminating orgau uuder a microscope, covered by a thiu glass cover. When the cover is lifted so as to admit a little air, the cells become lumiuous. We may add that the name "firefly" is a misuomer, as the "lightning bug" is a true beotle, belouging in the natural order caleoptera, and in the family