Department of Plant Physiology. 55 



Of the graduate students, many have been permitted to devote a certain 

 part of their time to advanced courses, but the total number of hours per 

 week taken by majors and minors has exceeded 160. 



During the second semester the courses and registrations were as 

 follows : 



Physiology 8b — 4 hours — 14 



Physiology 3b — i hour — 30 



Seminar lob — i hour — 13 



Physiology 17b — i hour — 8 



Research (Majors or Minors) — 2^ 



The remarkable development of the graduate work alone has taxed the 

 facilities of the Department. The work has, however, already yielded 

 gratifying results, but it has necessitated the restriction of registration 

 in courses. During the past year only two thirds of the students applying 

 for course 8 were accommodated (22), while in course 7 little more than 

 one half (22) were permitted to enter upon the work. This restriction 

 of registration is absolutely necessary, although it entails a hardship upon 

 the department in the development of its advanced work in the years 

 following. As this report goes in, the indications are that there will be 

 in the neighborhood of 75 applications for course 7 during 191Q-11, a 

 figure far exceeding the estimates made by this department to indicate 

 the probable rate of increase during the next ten years. Under the 

 conditions mentioned it has been impossible to develop several lines of 

 teaching toward which the department is looking, notably that in fer- 

 mentation and zymology and special ecology. 



investigation. 



In consideration of the amount of time devoted by the staff to teaching. 

 the work of investigation has progressed most satisfactorily. The follow- 

 ing topics are in part those mentioned in previous reports as under study 

 and in part are entirely new : 



Nutrition studies. — i. Considerable data have been accumulated with 

 respect to the action of nutrient solutions of different composition upon 

 plant growth, with the view of securing facts permitting a better interpre- 

 tation of the effects of soil solutions. 



2. The relation of plants to single nutrients or to preponderance of 

 a particular nutrient has received special attention as preliminary to the 

 more complete study of antagonistic action. 



3. The antidoting effect or antagonistic action of different mineral con- 

 stituents of the soil solutions has been extensively investigated by Mr. 



