PHYSICAL NATURE OF ANIMAL LIGHT 



BTJNSEN FLAME LINES 



to A = 0.44|ti). Young (1870) first recorded the limits of 

 the firefly spectrum as a little above C (A. = .6563/*) to 

 F (A ^ .4861/*). Since then a number of luminous forms 

 have been examined and all are found to give short con- 

 tinuous spectra (not crossed by light or dark bands or 

 lines) lying in different color regions. Thus, Conroy 

 (1882) examined the glowworm (Lampyris noctiluca) 

 light and observed a band extending from A = 0.518/* to 

 A = 0.656/*. Dubois (1886) states that the spectrum of 

 Pyrophorus noctilucus, the West Indian "CucuUo," ex- 

 tends from slightly further than the Fraunhofer B line 

 to the F line, while Langley and Very (1890), working 

 on the same form, placed the limits at A = 0.468/* to 



