EVOLUTION BY Cfilorelia: II 429 



tions of oxygen. I wonder if you also have it at a very much higher concentration. 

 We find that this fluorescent outburpt definitely decreases very much. Is that also 

 true of your oxygen outburst? 



R. A. Olson : I think the last figure shows these fluorescent effects. 



Brown : I want to make sure I did not misinterpret something by being amazed 

 at the evidence of these data. Your spike never does exceed the maintained steady- 

 state rate? 



R. A. Olson : That is right. The spike per se only closely approaches it. 



Brown : This is not reconcilable with the manometric data which were discussed 

 previousl}-. 



Brackett: Not unless the manometric data were obtained under conditions 

 which depress the sustained rate. 



Emerson: The conditions are extremely different, since here in Dr. Olson's 

 experiment there are hardly any sustained rates at all. The manometer is usable 

 for longer periods; in fact, for indefinite periods of time. 



Brackett : I am glad you said that. We talk about sustained rates as those that 

 follow and are influenced bj^ CO2. From your standpoint, these are quite short-term 

 phenomena. 



Rosenberg : Do you know the number of micromoles of oxygen consumed in this 

 vallej' between the spikes as related to the amount of chlorophyll present? This 

 might help us in comparing the luminescence state tomorrow. 



Brackett: We have made rough calculations. It is very small. Even the first 

 burst under this more limited condition requires only a small fraction of the chloro- 

 phyll molecules. 



Rosenberg : But that is the burst size? 



Brackett: That is the burst size. The depression is much smaller. I thought \ou 

 were asking about the negative reaction. 



References 



1. Blinki, L. R., and Skow, R. K., Proc. Natl. Acad. Sci. U.S., U, 413 ri938). 



2. Franck, J., Pringsheim, P., and Lad, D. T., Arch. Biochem., 7, 103 (1945). 



3. van der Veen, R., Physiol. Plantarum, 2, 287 (1947). 



4. Allen, F. L., and Franck, J., Arch. Biochem. and Biophys., 58, 124 (1955). 



5. Damaschke, V. K., Rothbuhr, L., and Todt, F., Z. Naturforsch., 10, 572 



(1955). 



6. Wassink, E. C, and Katz, E., Enzymologia, 6, 145 (1939). 



7. Strehler, B. L., and Arnold, W. J., /. Gen. Physiol, 34, 809 (1951). 



8. Waesink, E. C, and Rombach, J., Koninkl. Ned. Akad. Wetenschap. Proc, 



57, 493 (1954). 



9. Strehler, B. L., Arch. Biochem. and Biophys., 43, 67 (1953). 



10. Gaffron, H., Symposia Soc. Gen. Microbiol., 4, 152 (1954). 



11. Gaflron, H., and Rosenberg, J., Naturwiss., 12, 354 (1955). 



12. Lumry, R., Spikes, J. D., and Eyring, H., Ann. Rev. Plant Physiol., 5, 271 



(1954). 



13. KolthofT, I. M., and Jordan, J., J. Am. Chan. Soc, 75, 4869 (1953). 



14. Olson, R. A., Brackett, F. S., and Crickard, R. G., /. Gen. Physiol, S2, 681 



(1949). 



15. Allen, F. L., Arch. Biochem. and Biophys., 55, 38 (1955). 



