550 PROTOPLASM 



Getman, F. H., and F. Daniels: "Outlines of Theoretical Chemistry," 

 New York, 1931. 



Haas, A. R. C: Acidity of plant cells, Jour. Biol. Chem., 27: 232 (1916). 



Hall, N. F.: Modern conception of acids and bases, Jour. Chem. Ed., 7: 

 782 (1930). 



HiLDEBRAND, J. H. : " SolubiUty," New York, 1924. 



: The liquid state. Science, 80: 125 (1934). 



KiLPATRiCK, M.: The teaching of the theory of dissociation of electrolytes, 

 Jour. Chem. Ed., 9: 840, 1010, 1226 (1932). 



Lewis, G. N.: The ionic theory, Zeit. Phijsik. Chem., 70: 212 (1909). 



: Dissociation of strong electrolytes, Jour. Am. Chem. Soc., 34: 1631 



(1912). 



LowRY, T. M.: Theory of acids and bases. Trans. Faraday Soc, 26: 45 

 (1930). 



McCrudden, F. H.: Hydrogen ion concentration, U. S. Public Health 

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MiCHAELis, L.: "Effects of Ions in Colloidal Systems," Baltimore, 1925. 



: "Hydrogen Ion Concentration," Baltimore, 1926. 



NoYES, A. A.: Electrical conductivity of aqueous solutions. Pub. 63, Car- 

 negie Inst., Washington (1907). 



OsTWALD, W.: " Entwickelung der Elektrochemie," Leipzig, 1910. 



Perley, G. A.: Measurement of hydrogen ion concentration. Trans. Am. 

 Inst. Chem. Eng., 29: 1 (1933). (See also Leeds and Northrup Com- 

 pany, "Measurement of Hydrogen Ion Concentration.") 



Biological Systems 



Atkins, W. R. G.: Hydrogen ion concentration of plant cells, Sd. Proc. 



Roy. Dublin Soc, 16: 414 (1922). 

 Bailey, I. W., et al.: Hydrogen-ion concentration in vital staining. Jour. 



Gen. Physiol, 14: 363 (1931). 

 Cannon, W. B.: "Bodily Changes in Fain, Hunger, Fear, and Rage," New 



York, 1929. 

 Chambers, R.: Intracellular hydrion concentration, Biol. Bidl., 56: 369 



(1929). 

 et al. : Hydrion concentration of root-hair cells. Jour. Cell. Comp. 



Physiol, 2: 105 (1932). 

 Crozier, W. J.: Intracellular acidity in Valonia, Jour. Gen. Physiol, 1: 



581, 1919. 

 KoLTHOFF, I. M.: " Colorimetric and Potentiometric Determination of pH," 



New York, 1931. 

 KuRZ, H.: pH and plant distribution, Am. Nat, 64: 314 (1930). 

 Mevius, W. : Pflanzenwachstum, Naturwiss. u. Landwirtsch., 11: 1 (1927). 

 Reiss, P.: "Le pH Interieur Cellulaire," Paris, 1926. 

 Seifriz, W., et al: A slime mould pigment as indicator of acidity, Proto- 



plasma, 23: 175 (1935). 

 Small, J.: Hydrogen-ion concentration in plant cells and tissues, Proto- 



plasma Monog., 2 (1929). 



