Note 37 — Chapter VII · LIGHTNING-BUGS.
Reading edition
Page 55. The spectrum of the light of comparatively few of these beetles has been examined. That of Photinus was found by Professor C. A. Young, the astronomer, to be continuous without lines, and to extend from Fraunhofer’s line C in the scarlet, to about F in the blue.
Mr. Meldola examined the spectrum of the light of the glow-worm some years ago, and found that it was continuous, being rich in blue and green rays, and comparatively poor in red and yellow.