ACKNOWLEDGMENT 



It has become very difficult of late for any worker to know all 

 that has been recorded about any group of animals. Even such a 

 restricted subject as social behaviour in insects has by now an 

 immense literature. It is quite impossible for any one worker to 

 have made personal observation on all the species or to have seen 

 all the varieties of behaviour which have been recorded. Any of 

 my entomological colleagues who read this work will be aware 

 how far I have drawn on the writings of naturalists of many 

 countries. I have not thought it necessary to give references to the 

 literature in the text, but I have often mentioned the name of the 

 worker who first recorded some of the more striking facts. 



My thanks are due to the University of Hawaii Press for per- 

 mission to quote the extract from Insects of Hawaii by E. C. 

 Zimmermann, Volume V, which appears on page 126. 



I am indebted to my colleague Dr. N. WalofT for reading and 

 criticising the first draft of the book. 



O.W.R. 

 London, February, 1953 







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