X CONTRIBUTORS 



G. Meijer, Philips Research Laboratories, Eindhoven, The Nether- 

 lands 



Colette Nitsch, Laboratoire du Phytotron, Gif-sur-Yvette (S. et 

 O.), France 



J. P. Nitsch, Laboratoire du Phytotron, Gif-sur-Yvette (S. et O.), 

 France 



Gerald Oster, Department of Chemistry, Polytechnic Institute of 

 Brooklyn, Brooklyn, New York 



Oscar H. Paris, Jr., Department of Zoology, University of Cali- 

 fornia, Berkeley, California 



Colin S. Pittendrigh, Biology Department, Princeton University, 

 Princeton, New Jersey 



Kenneth S. Rawson, Zoology Department, University of Wisconsin, 

 Madison, Wisconsin 



Roy M. Sachs, Department of Floriculture, University of California, 

 Los Angeles, California 



Frank B. Salisbury, Department of Botany and Plant Pathology, 

 Colorado State University, Fort Collins, Colorado 



Power B. Sogo, Radiation Laboratory, University of California, 

 Berkeley, California 



Irwin Spear, Department of Botany, University of Texas, Austin, 

 Texas 



Beatrice M. Sweeney, Division of Marine Biology, Scripps Institu- 

 tion of Oceanography, La Jolla, CaUfornia 



N. E. Tolbert, Department of Agricultural Chemistry, Michigan 

 State University, East Lansing, Michigan 



Gordon Tollin, Radiation Laboratory, University of California, 

 Berkeley, California 



E. H. Toole, Agricultural Research Service, United States Depart- 

 ment of Agriculture, Beltsville, Maryland 



P. F. Wareing, Department of Botany, University College of Wales, 

 Aberystwyth, Great Britain 



E. C. Wassink, Laboratory of Plant Physiological Research, Agri- 

 cultural University, Wageningen, The Netherlands 



Lemen J. Wells, Department of Anatomy, University of Minnesota, 

 Minneapolis, Minnesota 



Frits W. Went, Missouri Botanical Garden, St. Louis, Missouri 



