The sense organs are the logical starting point for the investigation of 

 behavior in any animals, as well as for attempts to exploit the special sensory 

 capacities of animals in perfecting new technologies for human purposes. 

 That is why the contributions brought together in this book are particularly 

 significant at this time. They summarize the present "state of the art" in re- 

 search on some of the best underwater sensing systems ever evolved. 



In soliciting and discussing contributions from many scientists, we found 

 general agreement that a wide-ranging coverage, leading toward perspectives 

 on currently unsolved problems, would be most useful. Consequently, a 

 sizeable representation of the behavioral and natural history aspects of 

 elasmobranchs has been included, along with the strictly anatomical and 

 physiological studies. Observations from people with long and extensive 

 fisheries experience, but virtually no previously written records about it, 

 seemed important for their clues to problems that physiologists might well 

 investigate. Studies dealing with the effects of confinement upon the sensory 

 apparatus of sharks also seemed important for future laboratory investiga- 

 tors. It will be readily apparent to those with experience in this field why the 

 title refers to sensory biology, rather than strictly sensory physiology. We 

 hope this will help to emphasize the many important observations within the 

 sphere of natural history that remain to be investigated on a physiological 

 level. 



It is a pleasure to acknowledge our indebtedness to Drs. Charles 

 Woodhouse, Jr., and Bernard Zahuranec of the Oceanic Biology Program of 

 the Office of Naval Research, who originally suggested the book, and to Drs. 

 Ronald Tipper and Eric Shulenberger who have continued to provide ONR's 

 support, without which this volume could not have materialized. Mr. Stanley 

 Smith and Mrs. Sara Curry, of the Editorial Branch of the Naval Research 

 Laboratory, have given us invaluable guidance on editorial matters, and Mrs. 

 Curry has patiently and expertly guided the final preparation of the material 

 for the printers. Mr. DeWitt Darr, Sr., and Mrs. Dolores Robbins, of the 

 Graphic Arts Branch, NRL, have ably and helpfully overseen the layout and 

 production aspects of the volume. 



Finally, we welcome this chance to thank again our colleagues who made 

 contributions to the book. In addition to those who wrote chapters, our 

 thanks include others who were generous in enthusiasm and helpful sug- 

 gestions, but who found themselves with conflicting commitments so that 

 they could not contribute more explicitly. In the end, whatever values this 

 book may have are the result of the sustained efforts of all these people. 



EDWARD S. HODGSON ROBERT F. MATHEWSON 



Department of Biology Director Emeritus 



Tufts University Lerner Marine Laboratory, 



American Museum of Natural History 

 Director, Tice Biological Laboratory 



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