Chromatic Transients in the Photosynthesis of a Green Alga.

Characteristic variations of 02 production have been observed on changing the illumination of photo- synthetic tissue from one wave length to another, even though the steady state of photosynthesis became the same in each case. These were designated "chro- matic transients" (1). They were first found in red algae (e.g., Porphyra) where they amounted to some 10 to 15 % of the steady rate, on alternating the illumi- nation from 675 mnu (chlorophyll a absorption peak in the living tissue) to 540 or 560 mA (phyco-erythrin maxima).