468 



S. S. Brody and M. Brody 



PRUNUS VIRGINIANA 

 DARK GREEN LEAF 



550 600 650 



WAVELENGTH, m;. 



750 eoo 



Fig. 12 Fluorescence spectra excited 

 at 436 m\i. 



4S0 500 550 600 650 700 750 C 



WAVELENGTH.m* 



Fig. 13 Fluorescence spectra 

 excited at 436 mji. 



emission from the monomer increases with age, the increment of aggregate 

 emission far exceeds it. After about 48 hours in the light (the time, of 

 course, depends upon such factors as the density of the culture, the intensity 

 of light, etc. ), the monomer band becomes just an inflection on the short 



EUGLENA GRAC. (Z) 

 2 DAYS 



N, TEMP. 



ROOM TEMP. 



EUGLENA GRAC. IZI 

 3 DAYS 



Nj TEMP. 

 - ROOM TEMP. 



5M 



K 1 



550 600 650 



WAVELENGTH, n 



550 600 650 



WAVELENGTH, mp 



Fig. 14 Fluorescence spectra excited 

 at 436 myi. 



Fig. 15 Fluorescence spectra 

 excited at 436 mji.. 



wavelength side of the aggregate band and is soon completely masked. Con- 

 sequently in Euglena , aggregate fluorescence exceeds monomer fluorescence 

 during the major portion of the organism's life. These fluorescence 

 characteristics also obtain for Porphyridium . It is of interest to note, that 

 in the one organism of this type that we have examined - Porphyridium - 

 the "Emerson Effect" occurs at relatively short wavelengths (20,21,22); Brody 

 and Brody (5,8, iCf),, suggested that the disproportion of aggregate and mononner 

 at longer wavelengths does not permit the two photochemical reactions which 

 they postulated, to occur efficiently. 



