E. J. Russell and H. B. Hutchinson 



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predominates over the white in the untreated soil, but not in the 

 toluened soil. Where toluene is left in, however, the white streptothrix 

 slowly suffers. Only three of the bacteria observed are killed by the 

 short action of toluene — B. jiuorescens, 17 and 18. 



The effect of heat is much more drastic. Streptothrix, moulds, 

 B. mycoides, jiuorescens, zopfii and others are killed, leaving as survivors 

 only 8 to 11, 13, 12, 16, 7, of which 8 to 11 and 13 much outnumber 

 the rest. The flora of the heated soils is thus fairly simple. 



Table 12. Relative proportions of colonies on the gelatine plates. 

 (1) Immediately after partial sterilisation*. 



* Pending complete identifications some of the organisms are provisionally designated 

 by numbers. 



