126 INFLUENCE OF ARSENIC ON BACTERIAL ACTIVITY 



is exerted in soil which had been inoculated with solutions heated 

 just above that point which Cunningham and Lohnis found to be 

 the thermal death point of soil protozoa. 



REFERENCES. 



Greaves, J. E.: The Occurrence of Arsenic in Soils (Bichem. Bull., 1913, ii, 519- 

 523). 



Greaves, J. E.: Some Factors Influencing Ammonification and Nitrification in 

 Soil (Centr. f. Bakt., Bd. xxxix, Abt. II, 1913, 542-560). 



Greaves, J E.: Stimulating Influence of Arsenic upon the Nitrogen-fixing Organ- 

 isms of the Soil (Journal Agricultural Research, 1916, vi, 389-416). 



