SPECTRAL ENERGY CURVES OE UGHT EMITTED BY VARIOUS SPECIES. 23 



In view of the fact that the color of the light oi Photinus consanguineus and 

 Photinus scintillans appears to be more variable than that of other fireflies, 

 it would be of interest to determine whether they emit light composed of two 

 bands, of which the one is yellow and the other is orange-red. A large dis- 

 persion would be required; and plates sensitized so as to be more uniform 

 in their action in the red and yellow would be useful. 



Table 2. 



Having but one density curve (Fig. 8, ®, — ^, — ®) of Photinus scintillans, 

 and this one being too much overexposed to work out the central part of the 

 curve, no exact value of the maximum emission of this insect has been 

 obtained. The density curve is symmetrical with a similar one of the 

 Photinus consanguineus, and, in view of the fact that to the eye there is no 

 marked difference in the color of the hght (the flash) emitted by these two 

 species, the maximum emission of scintillans is taken to be the same as that 



