Page:Popular Science Monthly Volume 77.djvu/127

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PHYSIOLOGIC LIGHT
121

to from seven to fourteen males seems to be about the proportion. The same condition appears to hold with other species of Lampyridæ also. King states that the female of the Texan form Pleotomus pallens is much more luminous, and rather less active than the male. In addition to the photogenic power, the common firefly is possessed of a strong and characteristic odor; Carradori also notes that the Italian luciole has an odor like that of garlic. Many insects indeed possess odors, but that of the Lampyridæ appears to be especially characteristic of the group.

In conclusion, we may say that while a vast amount of work has already been done on this interesting problem, the production of physiologic light still presents many mysteries which science has yet to explain. Nature keeps her secrets well, but this one seems well worthy of solution; the immediate practical and economic importance may not be so great as has been sometimes assumed, but it is a problem of interest alike for the physicist, the chemist, the biologist and the entomologist, and the scientific world awaits its solution with much curiosity.