60 



JAMES M. SHERMAN 



TABLE XIII 

 Effect of Colpoda cucullus upon the number of bacteria in soil 



Test 1 



Test 2 



1,640,000,000 

 2,160,000,000 



1,900,000,000 



2,640,000,000 

 2,500,000,000 



2,570,000,000 



Test 3 



620,000,000 

 670,000,000 

 820,000,000 

 780,000,000 



722,500,000 



770,000,000 

 730,000,000 

 810,000,000 

 700,000,000 



752,500,000 



Results with Balantiophorus elongatus 



The results obtained with Balantiophorus elongatus are similar 

 to those with Colpoda cucullus; in liquid cultures the bacteria 

 are definitely suppressed while in soil no such action is evident. 

 The slight difference noted in Table XV is easily within the limits 

 of experimental error. Only one test of B. elongatus in soil is 

 here reported; since this organism is not active in soil (Part III) 

 it is obvious that it could not function as a bacterial limiting 

 factor. 



TABLE XIV 

 Effect of Balantiophorus elongatus upon the number of bacteria in soil extract 



