168 JAMES M. SHERMAN 



were found in every case except in the one treated with 10 per 

 cent carbon bisulphide in which no amoebae were observed. 

 In all of these soils Monas sp., Dimorpha radiata and Flagellates 

 A and B were present. 



Several attempts were made without success to demonstrate 

 a stimulation of the protozoa, similar to that of the bacteria, 

 subsequent to the application of volatile antiseptics to the soil. 

 Moore (1912) in an address on the "Micro-organisms of the Soil" 

 stated that results obtained in his laboratory indicated that the 

 protozoa in soil not only withstood the action of antiseptics 

 but that they might be increased by such treatment. Wood- 

 ruff (1908) has shown that the multiplication of infusoria may 

 be stimulated by small doses of alcohol. The dilution method 

 for the determination of the number of protozoa is far too crude 

 to measure small differences so the fact that it failed to demon- 

 strate any increase in the number of protozoa following the 

 apphcation of volatile antiseptics to soil cannot be considered 

 of much importance. 



Discussion 



From the results herein reported it may be concluded that 

 volatile antiseptics in the amounts used in practice do not free 

 the soil from protozoa. The active soil protozoa not only sur- 

 vive, but multiply rapidly and again attain their normal num- 

 bers, usually within a month after treatment. It is difficult 

 to explain the failure of Russell and Hutchinson to find protozoa 

 in the soils which they treated. They noted the survival of 

 certain flagellates which they do not, however, associate with 

 the "detrimental factor." The failure of these workers to find 

 ciliates and amoebae may be due to insufficient samples. The 

 ciliates and amoebae are greatly reduced by the treatment of 



