PREFACE 



A Symposium on "Light and Lite" was held at The Johns Hopkins 

 University under the sponsorship ot the McCoUum-Pratt Institute 

 on March 28-3 L 1960. This volume contains the papers and informal 

 discussions presented during the Symposium. 



In the planning of the present Symposium we attempted, as in 

 previous symposia, to bring together scientists from a number of 

 different disciplines. Unfortunately time and printing limitations 

 prevented the consideration of a number of interesting photobiological 

 problems. 



I would like to acknowledge the active participation of the members 

 of the McCollum-Pratt Institute and of the Department of Biology 

 in the planning of the Symposium. Many of the speakers on the 

 program were helpful in suggesting areas or specific topics that should 

 be discussed. It is also a pleasure to acknowledge the valuable contri- 

 butions of the following moderators: Dr. Albert Szent-Gyorgyi, Dr. 

 James Franck, Dr. William Arnold, Dr. C. B. van Niel and Dr. 

 H. K. Hartline. 



The support of a limited number of foreign investigators as parti- 

 cipants in the Symposium was made possible through the generous 

 aid of the National Science Foundation. Unfortunately, insufficient 

 funds prevented the attendance of a larger number of participants 

 from great distances. 



We hope, however, that the published book will be of value to 

 all investigators interested in photobiological processes. 



W. D. McElroy 



Director, McCollum-Pratt Institute 



