PLANT PHYSIOLOGY PRESENT PROBLEMS 



BY BENJAMIN MINGE DUGGAR 



[Benjamin Minge Duggar, Professor of Botany, University of Missouri, b. 

 Gallion, Alabama. B.S. Mississippi Agricultural and Mechanical College, 1891; 

 A.B. Harvard University, 1894; M.S. Alabama Polytechnic Institute, 1892; 

 A.M. Harvard, 1895; Ph.D. Cornell, 1898; Postgraduate, Alabama Polytech- 

 nic Institute, 1891-92; Harvard, 1893-95; Cornell, 1896-98; Leipzig and 

 Halle, 1899-1900. Assistant Professor of Botany, Cornell University, 1900-01; 

 Plant Physiologist, Bureau of Plant Industry, U. S. Department of Agriculture, 

 Washington, 1901-02. Member of the Society for Plant Morphology and 

 Physiology, Botanical Society of America, Deutsche botanische Gesellschaft, 

 American Association for the Advancement of Science. Author of articles for 

 botanical magazines, Experiment Station bulletins.] 



To the very year one century has elapsed since Theodore de Saus- 

 sure published his remarkable investigations relating to the nutrition 

 of plants and to the influences upon plants of certain well-known 

 physical forces. Although preceded by the publications of Duhamel, 

 Hales, Ingen-Housz, and Senebier, as well as by those in a somewhat 

 different line, by Konrad Sprengel and others, we may look upon 

 the work of de Saussure as a wonderful production for his time and 

 as strikingly indicative of the status of plant physiological problems 

 a century ago. His paper may be regarded in a sense as the original 

 charter or constitution of plant physiology. Fortunately, it is as- 

 signed to an eminent and experienced botanical historian to recite 

 the amendments which mark the wonderful growth of this historic 

 instrument. There remains, therefore, the task of suggesting some 

 directions of future growth. 



No distinction need here be made between those problems which 

 are readily seen to involve the closest work in such other sciences as 

 physics and chemistry and those which do not show a relationship 

 so close. There is certainly much in physiology which must be based 

 upon physics and chemistry, but when dealing with the causes of 

 the activities of living organisms, it is in relatively few cases that 

 explanations may ever be offered in terms of physics and chemistry 

 alone. Nor is it possible to offer such explanations without the 

 assistance of these sciences. The progress of the work in physiology 

 is indissolubly bound up in the development of other sciences. The 

 benefits are, however, mutual, and as physiology acknowledges the 

 fundamental importance jaf these related sciences, they in turn must 

 acknowledge the important contributions, often of fundamental 

 nature, which have resulted through physiological investigation. 



In such a paper it would be impossible to do more than outline 

 briefly some of the relationships of special problems which, for one 



