REFERENCES TO SOME PAPERS DESCRIBING METHODS 



ON WHICH THE PLAN FOR THIS 



PROJECT IS BASED.* 



1910. Schreiner, O., and J. J. Skinner. 



Ratio of phosphate, nitrate and potassium on absorption and 

 groAvth. Bot. Gaz. 50: 1-30. 1910. Idem. Some effects of a 

 harmful organic soil constituent. U. S. Dept. Agric. Bur. Soils 

 Bull. 70. 1910. 



1914. Tottingham, W. E. 



A quantitative chemical and physiological study of nutrient 

 solutions for plant cultures. Physiol. Res. 1 : 133-245. 1914. 



1915. Shive, J. W. 



A study of physiological balance in nutrient media. Physiol. 

 Res. 1 : 327-397. 1915. 



1916. McCall, A. G. 



The physiological balance of nutrient solutions for plants in 

 sand cultures. Soil Sci. 2: 207-253. 1916. Idem. The physio- 

 logical requirements of wheat and soy beans growing in sand 

 media. Proc. Soc. Prom. Agric. Sci. 1916: 46-59. 1916. 



1917. Hibbard, R. P. 



Physiological balance in the soil solution. Michigan Agric. 

 Exp. Sta. Techn. Bull. 40. 1917. 



Shive, J. W. 



A study of physiological balance for buckwheat grown in 

 three-salt solutions. New Jersey Agric. Exp. Sta. Bull. 319. 

 1917. 



1918. Livingston, B. E., and W. E. Tottingham. 



A new three-salt nutrient solution for plant cultures. Amer. 

 Jour. Bot. 5: 337-346. 1918. 



*'0f course a large number of papers might be mentioned in this list, as 

 bearing in one way or another upon this project. From the point of view 

 of the logical analysis of the problem the papers cited heFe will be specially 

 valuable, and "numerous other literature references may be obtained from 

 them. Tottingham's bibliography will be found very useful in connection 

 with the general proposition of controlled chemical environment as far as 

 the root system of the plant is concerned. 



