348 



ANNUAL REPORT SMITHSONIAN INSTITUTION, 1911. 



Maulik ( 61a ) have recently published some results similar to those of 

 Muraoka. 



Judged from the fact that the light produced by many chemilumi- 

 nescent reactions appears greenish to the human eye, it would seem 

 that these should give spectra approximating that of the firefly [see 

 Radziszewski ( 60 ), Trautz ( 67 )], but in view of the facts that the light 



0.39/x 



1. Portion of the visible solar (grat- 



ing) spectrum. 



2. Spectrum of Pyrophorus nocti- 



lucus (Langley and Very- 9 ). 



3. Spectrum of Lampyris nuctiluca 



(Conroy <>). 



4. Spectrum of Photinus pyralis 



(Ives and Coblentz 31 , Co- 

 blentz 5 »> 6 ). 



5. Spectrum of Photinus consan- 



guineus (Coblentz 5 *' 6 ). 

 G. Spectrum of Photuris pennsyl- 

 vanica (Coblentz 5 *> 6 ). 



7. Spectrum of Phcngodcs lalicollis 



? (original). 



8. Spectrum of Bacterium phospho- 



reum, B. phosphorescens, and 

 Bacillus photogenus (Mo- 

 lisch 52a ; Mangold 45 ). 



9. Spectrum of Photobacterium in- 



dkum (Barnaid 2 *). 



10. Spectrum of Mycelium X (Mo- 



lisch 55a ; Mangold 45 ). 



11. Spectrum of luminous bacteria 



from sea fish (Forster; Man- 

 gold 45 ). 



12. Spectrum of Agaricus (Ludwig; 



Mangold «). 



13. Fluorescent spectrum of fluor- 



escent material (luciferesceine) 

 from Photinus pyralis (Co- 

 blentz si » 5 a). 

 Numbers 2 to 7 inclusive, are from 

 insects. Numbers 8, 9, and 11 are 

 from microorganisms. Numbers 10 

 and 12 are from fungi. 



Only the extreme ends of the bands 

 are shown, no attempt being made to 

 indicate the relative density of differ- 

 ent portions of the spectra; thus in 7 

 the maximum intensity is confined to 

 a very much narrower band than 

 shown for the whole spectrum. 



Fig. 1.— Spectral ranges of light from different organisms. 



emitted in most of these cases is very feeble and that the human eye 

 is decidedly more sensitive to the greenish tones than to others, it may 

 be simply that the amount of radiation, other than that giving the 

 sensation of green, produced by these reactions is insufficient to cause 

 the human retina to respond. However, it is difficult to class the 

 production of light by living forms as other than a vital expression of 



