COLLABORATING EDITORS 



Farrington Danikls, Professor of Physical C'hemistry, University of 

 Wisconsin, Madison 



Alexander Hollaender, Director, Biology Division, Oak Ridge 

 National Laboratory, Oak Ridge 



John R. Loofbourow, Professor and Executive Officer, Biology Depart- 

 ment, Massachusetts Institute of Technology, Cambridge 



Arthur W. Pollister, Professor of Zoology, Columbia University, 

 New York 



Lewis J. Stabler, Professor of Field Crops, University of Missouri, and 

 Agent, U.S. Department of Agriculture, Columbia 



