224 PHOTOSYNTHESIS 



illuminated, does produce hydrogen peroxide. The latter accumulated to 

 a concentration of about N. 0.001 when there was present in the nutrient 

 solution hydrocyanic acid in N. 0.01 concentration. It was found that 

 the hydrogen peroxide was not the result of photosynthetic activity, how- 

 ever, but was produced by the photo-oxidation of the chlorophyll. 



