Jan., 1921] Translocation of Carbohydrate Materials 99" 



when the acidity is nearer to the optimum activity of invertase 

 (about 10^'"", Hober). Sucrose is mostly at its highest during 

 the growing period and early dormant period, when the acidity 

 is rather below the optimum for sucrase. In fact, the data 

 on acidity show in general a correlation of acidity to the 

 activity of enzymes that are involved in the changes of the 

 carbohydrate materials and their accumulation in plant tissues. 



The writer is indebted to Professors J. F. L^^man and T. G. 

 Phillips for helpful suggestions in analytical work and especially 

 to Prof. H. C. Sampson for numerous suggestions on problems 

 and interpretation of results. 



LITERATURE CITED. 



1. Mer, E. 189 1. Repartition hivernale de ramidon dans les plantes ligneuses. 



Comp. Rend., T. 1, pp. 964-966. 



2. Rosenberg, O. 1896. Die Starke der Pflanzen im Winter. Bot. Centbl. Bd. 



66, s. 964-966. 



3. 1909. Bui. U. S. Dept. Agri. No. 107. 



4. Darwin, F., and Acton, H. 1909. Practical physiology of plants, p. 258. 



5. Abderhalden, E. 1910. Handbuch der Biochemischen Arbeits-methoden s. 270. 



6. Hober, R. 1914. Physikalische Chemie, s. 271. 



7. Butler, O. R., Smith, T. O., and Curry, B. E. 1917. Physiology of the Apple. 



Xew Hampshire Col. Agr. Expt. Sta., Tech. Bui. No. 13. 



8. Sherman, H. C, Thomas, A. W., and Baldwin, M. E. 1919. Influence of hydro- 



gen ion concentration upon enzymic activity of three typical anvlases.. 

 Jour. Am. Chem. Soc, Vol. 41. No. 2, pp. 231-235. 



