SOIL MICROBIOLOGICAL EQUILIBRIUM 



759 



the inoculation of soil with protozoa may lead to a decided depression 

 in the numbers of bacteria; 07 however, so far no definite proof has been 

 submitted that the introduction of protozoa actually depresses bio- 

 chemical processes in the soil important to soil fertility; the meagre 



293 323 



Fig. 71. Influence of protozoa upon the development of bacteria: U = un- 

 inoculated;T -f- W = toluene treated soil plus distilled water; T + F = toluened 

 soil plus hay-infusion, filtered through a Berkfeld filter; T + C - toluened soil 

 plus ciliates in hay-infusion; T + M = toluened soil plus mixed culture of pro- 

 tozoa and bacteria in hay-infusion (from Goodey). 



results available seem to point to the contrary, as shown elsewhere 

 (p. 338). 



Agricere and Baderiotoxin theories. The results of Schreiner, Shorey 

 and their associates seemed to indicate that the soil harbors certain 



87 Cutler, 1923 (p. 32). 



