66 
Psyche 
[March 
Acknowledgements 
Thanks are due to Dr. E. O. Wilson and Mr. J. M. Reichson for 
their reading of the manuscript. The author is also grateful to Miss 
N. K. Lind, who offered many useful suggestions. 
This work was supported by Grant No. GB7734 of the U. S. 
National Science Foundation (Dr. E. O. Wilson sponsor) and a 
grant from the Swiss National Science Foundation. 
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