Mar. 24, 1919 



Ainmonification of Manure in Soil 



323 



other hand, showed a much lower rate of increase and developed from an 

 initial plate count of 1,800,000 (see Table V, Experiment I) to a count 

 of 15,000,000 on the seventh day, an increase of 8.3 times the original 

 inoculation. The microscopic coimt on the seventh day showed 

 36,000,000 vegetative cells, an increase of 20 times the initial count. 

 In the four series Ps. caudatus showed its greatest increase in Experi- 

 ment III (Table IV), on the ninth day, when it showed a count 913 

 times greater than its initial count ; Ps. fluorescens registered its greatest 

 increase in Experiment IV on the fourteenth day, when it showed a 

 count 530 times higher than the original count; and B. cereus made its 

 greatest increase in Experiment IV (Table V) on the sixteenth day, 

 showing a count 29 times higher than the original. 



Table V. — Multiplication of B. ceretis inoculated into sterile manured soil 

 [Count indicates the numbers per gram of soil] 



Experiment No. and time since 

 inoculation. 



Experiment 1: 

 odays 



3 days 



sdays 



7 days 



Experiment II:'' 



odays 



sdays 



8 days 



17 days 



23 days 



Experiment III: 



odays 



2 days 



4 days 



6 days 



Sdays 



Experiment IV: 



o days 



2 days 



4 days 



6 days 



Sdays 



11 days 



12 days 



14 days 



i6days 



Plate count. 



,000,000 

 , 750,000 

 ,000,000 



600.000 

 000,000 

 000,000 

 000,000 



000,000 

 000,000 

 500,000 

 000,000 



000,000 

 000,000 

 500,000 

 000,000 

 000,000 

 000, 000 

 000. 000 

 000,000 



Microscopic count. 



Groups. 



Vegetative 

 cells. 



Spores. 



5,000,000 



6,000,000 



36, 000, 000 



2,000.000 

 2, 500,000 

 2, 500,000 

 2,500,000 



2,000,000 

 1, 500,000 

 2, 500,000 

 1, 500.000 

 2,000.000 

 2. 500,000 

 2. 500,000 

 3,000,000 



19,000,000 

 6,000,000 

 17,000,000 



18,000,000 

 II, 500,000 

 16,000,000 

 14,500,000 



5.000, 000 

 12,000, 000 

 11. 500.000 



9,000.000 

 13,000,000 

 12,000,000 

 IS, soo. 000 

 21,000,000 



Individuals. 



Vegetative 

 cells. 



" 1,800,000 

 9,000,000 

 3,000,000 

 50, 000, 000 



1 1,300,000 



<• 116,000 

 13,000,000 

 10, 500,000 

 15,500.000 



7, 500, 000 



o 103,000 

 II, 500, 000 

 13, 500,000 

 9, 500.000 

 4. 500, 000 

 6,000, 000 

 7,000,000 

 6,500,000 

 6, soo, 000 



Spores. 



None. 



23.000,000 

 6,000,000 

 18, 000, 000 



None. 



None. 

 33. 000. 000 

 16. 500,000 

 19,000,000 

 18,000,000 



None. 



30,000,000 

 24, 500, 000 

 27, 500,000 

 27,000,000 

 19,000,000 

 21,000, 000 

 26, 500, 000 

 32,000,000 



<» Computed from the number of organisms in the infusion used for inoculation. 

 & No microscopic count made. 



SOIL INOCULATED WITH A MIXTURE OF THE THREE ORGANISMS 



Table VII gives the results of placing the three organisms in compe- 

 tition one with another by inoculating flasks of sterile manured soil with 

 all of them together. Infusions were made from fresh cultures of each 

 organism and the strength of these infusions determined by the micro- 

 scopic method. After infusions of the proper strength had been obtained, 

 equal amounts of each were thoroughly mixed and i cc. of the mixture 



