CONTRIBUTORS ix 



Erna Halberg, The Medical School, University of Minnesota, Min- 

 neapolis. Minnesota 



Franz Halberg, The Medical School, University of Minnesota, Min- 

 neapolis, Minnesota 



Robert Whiting Harrington, Jr., Entomological Research Center, 

 Florida State Board of Health, Vero Beach, Florida 



J. Woodland Hastings, Division of Biochemistry, Noyes Laboratory 

 of Chemistry, University of lUinois, Urbana, Illinois 



Sterling B. Hendricks, Soil and Water Conservation Research 

 Division, Agricultural Research Service, United States Department 

 of Agriculture, Beltsville, Maryland 



William S. Hillman, Department of Botany, Josiah Willard Gibbs 

 Laboratory, Yale University, New Haven, Connecticut 



Alexander Hollaender, Biology Division, Oak Ridge National 

 Laboratory, Oak Ridge, Tennessee 



William P. Jacobs, Department of Biology, Princeton University, 

 Princeton, New Jersey 



Charles E. Jenner, Department of Zoology, University of North 

 Carolina, Chapel Hill, North Carolina 



Charles M. Kirkpatrick, Agricuhural Experiment Station, Purdue 

 University, Lafayette, Indiana 



William H. Klein, Division of Radiation and Organisms, Smith- 

 sonian Institution, Washington, D. C. 



Anton Lang, Department of Botany, University of California, Los 

 Angeles, California 



A. D. Lees, Univ. of Insect Physiology, Agricultural Research Coun- 

 cil, Cambridge, England 



James L. Liverman, Division of Biology and Medicine, U. S. Atomic 

 Energy Commission, Washington, D. C.^ 



James A. Lockhart, Kerckhoff Biological Laboratory, California 

 Institute of Technology, Pasadena, California 



Fausto Lona, Istituto Ed Orto Botanico, Universita degli Studi di 

 Parma, Parma, Italy 



Wayne J. McIlrath, Department of Botany, The University of 

 Chicago, Chicago, Illinois 



^ On leave from Texas Agricultural Experiment Station, College Station, 

 Texas. 



