﻿A NEW METHOD OF SEPARATING FUNGI FROM 

 PROTOZOA AND BACTERIA 



The investigations of Russell and Hutchinson, 1 Goodly, 2 

 Cunningham and Lohnis, 3 and others have stimulated the devel- 

 opment of a new branch of soil biology, namely, soil protozoology. 

 A problem of considerable interest in this field is the determination 

 of the effect of soil protozoa upon soil bacteria. Russell and 

 Hutchinson maintain that soil protozoa have a marked influence 

 on bacterial activity, and consequently soil protozoa may be 

 regarded as one of the limiting factors in soil fertility. The 

 criterion for measuring the effect of soil protozoa on bacterial 

 activity has commonly been the production of ammonia and 



In pursuing this problem, some preliminary experiments, one 

 of which was concerned with soil fungi, were carried on by the 

 writers. In view of the fact that fungi are capable of producing 

 ammonia, 4 their presence might mean an additional factor not 

 accounted for in measuring the effect of soil protozoa on soil 

 bacteria. So far as we have been able to ascertain, neither Russell 

 and Hutchinson nor other investigators dealing with similar 

 problems have taken into consideration the possible value of this 

 factor. Fungi are capable of producing ammonia, and until it has 

 been established that they do not alter the results of ammonia 

 production in the presence of bacteria in such experimental work, 

 it would seem a priori that their presence is undesirable. Since 

 a survey of the literature bearing on the subject offered neither 

 suggestions nor a solution of the difficulty, the authors attempted 

 to devise a method for the elimination of this factor. 



