340 PRINCIPLES OF SOIL MICROBIOLOGY 



diet, since they themselves cannot utilize the cellulose, unless it has 

 been previously decomposed by fungi. This symbiotic relationship 

 exists for at least some protozoa. We do not know as yet whether some 

 soil protozoa may be able to decompose complex organic substances; it is 

 known, however, that they can readily assimilate such soluble organic 

 and inorganic constituents as found in manure. 103 



103 Alexeiev, 1917 (p. 317). The relation of protozoa to reducion phenomena 

 in the soil is discussed by von Wolzogen Kuhr, C. A. H. Protozoa and the phe- 

 nomena of reduction in soil. Arch, voor de Suikerind. nederland. Indie., No. 

 27, 1125-1182. 1917. (Int. Rev. Sci. Pract. Agr., Agr. Int. and PI. Dis., 9: 788. 

 1918.) 



