The lightning bugs or fireflies which are seen so often on summer evenings in the country and among the trees in the parks of the city, are similar to the species of beetle called the glowworm in Great Britain, although the glowworm there does not give as much light as the firefly in America.

In reality it is only the female which is the lightning bug, for the male is not equipped with any lighting power. He has the bad habit of going out nights, and so the female has had to make use of her ability to make part of her body shine with a sort of a phosphorus green light .in order to show him the way home, very much as a dweller in a poorly-lighted street keeps a light in the window or on the porch to guide visitors or the late home-comer to the proper house. She seems to possess the power of moderating or increasing the light at will.

The most brilliant fireflies are found only in the warmer regions of the world. The ordinary firefly to which we are accustomed gives off a very much brighter light if placed in warm water. Fine print may be read by the light of one kind which is found in the West Indies; in Cuba the ladies have a fashion of imprisoning them in bits of netting or lace of a fine texture and wearing them as dress ornaments, and in Hayti they are used to give light for domestic purposes, eight or ten confined in a vial emitting sufficient light to enable a person to write, u