No. 510] PROBLEMS IN PLANT ECOLOGY 



377 



The temperature of the soil can be measured and 

 recorded with about as great ease as can that of the air. 

 But we meet here the same difficulties in regard to in- 

 terpretation. 



Finally, for a goodly number of ecological investiga- 

 tions, the bacterial flora of the soil must be investigated. 

 The agriculturists have made good progress here and we 

 may do well to follow them. The possibilities are very 

 great 



In conclusion I should like to call attention to what 

 appears to me to be the one great general need of ecolog- 

 ical work, namely, the need of quantitative studies. It is 

 only through such studies that the science of the relation 

 of the plant to its environment can make real progress. 



Discussion of Dr. Livingston's Paper. 

 Dr. Burns: I am heartily in accord with all Dr. Livingston has said, 

 and I have a lot of records of light readings, that I think I have had for 

 the past six or seven years, that I don 't know what to do with. Ah ecolog- 

 ical work, for instance, will dilate on rain force, and then leave that alone, 

 and presently suggest something entirely different. It seems to me that 



mum and minimum of light, and along this line I have been trying to work 



out and be succeeded by some other plant, but I have not got on very far. 



condition. Its effect on growth may be either unseen or apparent in some 

 outward manifestation. This article shows, by a careful analysis, that the 



a fungus,— the temperature factor as applied produced a substance which 

 inhibited growth of that fungus and finally stopped its growth. 



Professor Barnes : May I take this opportunity to say that I hope very 

 much some of the reforms will be adopted, not only by ecologists, but 

 also by some other members of the botanical fraternity. Mr. Harshberger 'a 



imagine. Our ideas have not always kept pace with the growth of our 

 language (laughter). It is greatly to be hoped that the language will not 

 be strained any farther. We need no extensive growth of that, and while 



