ACKNOWLEDGEMENTS 



I ACKNOWLEDGE with gratitude the help and stimulus that I have 

 received from many friends and experts, with whom I have 

 discussed different sections of this book. Among these I would 

 mention particularly Professor B. Hanstrom, who read the whole 

 of chapter 3 ; Professor M. Thomsen and Dr. Ellen Thomsen who 

 discussed the general plan with me ; Professor H. E. Heller who read 

 § 5.3 on electrolyte and water balance; Dr. J. A. Kitching, who 

 read §§ 4.1 and 5 and Sir Francis Knowles and Dr. D. B. CarUsle 

 who gave me much information on crustacean hormones and 

 discussed the nomenclature which has been adopted here and, in 

 part, in their own recent book. Professor J. E. Harris went far 

 beyond the duties of an Editor in encouraging me in every way 

 and not least in his penetrating discussion of fundamental 

 problems of hormone action. Though all these have saved the 

 book from many errors, I must accept sole responsibility for any 

 that remain, as I do for the selection, interpretation and presenta- 

 tion of the material. 



I am particularly indebted to Sir Francis Knowles for allowing 

 me to reproduce some of his beautiful coloured photographs of 

 chromatophores in Leander and to the publishers of Endeavour 

 for supplying copies of the blocks for these. My warm thanks for 

 permission to reproduce or adapt their figures are also due to 

 Dr. E. Thomsen and Dr. S. P. Carlson, who provided photographs 

 for Figures 2-3 and 3-19; to Dr. W. Junk of the Hague, for the 

 block of Figure 5-6, and to all the other authors and publishers 

 indicated in the legends and references, as well as to the following 

 pubhshers and sponsors of journals: 



Academic Press Inc. (Figs. 2-10, 4-10, 4-11, 5-10). 

 American Institute of Biological Sciences, Washington (Fig. 



3-23). 

 American Physiological Society (Figs. 3-7, 4-2, 4-3, 4-4, 4-5, 



5-9, 5-22). 



