228 THE BIOLOGY OF HYDRA : 1961 



results described here on the interaction of gkitathione with the 

 Hydra receptor may bear a relation to the functioning of some of 

 these other systems. 



ACKNOWLEDGEMENTS 



It is a pleasure to acknowledge the superb assistance that Mr. 

 John Bovaird has provided throughout this study. The criticisms 

 of this manuscript by Drs. J. F. Woessner, Jr., A. Phillips, E. L. 

 Chambers, and W. D. Dandliker are greatly appreciated. 



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