6 THE FIELD OF PLANT PHYSIOLOGY 



inadequate. Disagreements regarding the interpretation of experiments and 

 observations are often inevitable steps in the clarification of scientific generali- 

 zations. Controversies usually focus attention upon gaps in our factual infor- 

 mation. Frequently, therefore, they are stimulating to research, and often 

 lead to a further enrichment of human know^ledge. 



Without the knowledge of plant processes which has been slowly accumu- 

 lated through more than two centuries of observation, experimentation, and 

 critical evaluation by numerous workers in all parts of the world, this book 

 could never have been written. In spite of the patient labors of these many 

 workers vast gaps still exist in our understanding of the physiology of plants — • 

 gaps which are reflected in the necessarily inadequate treatment of many topics 

 in this book. The future of this science and all others lies in the hands of 

 the front-line investigators who wage a continual struggle for the extension of 

 human knowledge. 



Suggested for Collateral Reading 



Harvey-Gibson, R. J. Outlines of the history of botany. A. and C. Black. 



London. 191 9. 

 Libby, W. An introduction to the history of science. Houghton Mifflin 



Co. Boston. 191 7. 

 Nordenskiold, E. The history of biology. Translated by L. B. Eyre. 



Alfred Knopf. New York. 1928. 

 Sachs, J. History of botany. Translated by H. E. F. Garnsey. Revised by 



I. B. Balfour. Clarendon Press. Oxford. 1906. 



