328 



Journal of Agricultural Research 



Vol. XVI, No. 12 



of these tables show that either Ps. fluorescens or Ps. caudatus, or both, 

 almost invariably appeared on every sample plated and often constituted 

 as high as 15 or 20 per cent of the entire flora, while B. cereus was very 

 seldom observed; in fact, very few spore formers of any type were 

 recognized. It must be borne in mind that these data were obtained 

 from soil in which it was definitely determined that decomposition 

 processes were occurring. 



Table XI. — Comparison between numbers of Bacillus cereus and numbers of certain 

 non-spore formers in soil from Plot I. Soil manured and kept in the laboratory. 

 Series III 



HORSE MANURE 

 [Counts indicate number of colonies per gram of soil] 



cow MANURE 



58,000,000 

 73, 250,000 



497, 500,000 

 93,000,000 



102, 500,000 

 36, 250,000 

 43,000,000 

 17,500,000 

 40, 000. 000 

 96,000,000 



187,000,000 

 75,000,000 

 64,000,000 



Average. 



51,000,000 

 42,000,000 

 295,000,000 

 68,000,000 

 44, 250,000 

 27, 250,000 



45,500,000 



31,000,000 

 36, 500,000 

 49,500,000 

 53,000,000 

 125,000,000 

 46,000,000 



800.000 



1,000,000 



25, 000, 000 



2,000,000 



2,000,000 



None, 



None. 



None, 



500,000 



1,000,000 



I, 500,000 



10,000,000 



Trace. 



2 , 000, 000 

 2.000,000 

 12,000,000 

 3,000,000 

 3,500,000 

 1,000,000 

 1,000,000 

 2,000,000 

 5,000,000 

 5,000,000 

 1,000,000 

 2,000,000 

 None, 



3-9 

 4.8 

 4.2 

 4.4 

 7-9 

 4.0 

 2. 3 

 6.4 

 14. o 

 10. o 

 1.9 

 1.6 



a B. cereus did not appear on the plates. 



