EXPERIMENT STATION BULLETINS. 363 



AT WHICH STAGE OF THE PROCESS IS THE ASSOCIATE INFLUENCE MANIFESTED? 



It appears from the illustrations taken from the preceding tables, that 

 ill some instances the associate micro-organisms seem to exert an influence 

 at the beginning of the souring process; in some it appears later, even at 

 the end of the process; and, in still othei^s, the influence seems to be felt 

 throughout the process from beginning to end. 



The following tables will illustrate the varied influence of the associate 

 micro-organisms. 



The associate micro-organism in the first table has exddently carried 

 on its functions early in the process, and later seems to have held in check 

 the lactic micro-organisms. 



Time aftfT inoculation. hrs. 7 lirs. 24 lirs. 31 lirs. 48 lirs. o-i hr.s. 



rnlturf nil 14° 14° 14° 2o° 44° 44° 



Culture I m + IIIx 14° 14° 17° 2(1° 45° 61° 



Culture IIIx 14° 14° 14° 14° 41° (i9° 



In the next table the influence of the lactic micro-organisms is retarded 

 until the later stages of the process. 



Time after inoculation. hrs. 7 hrs. 23 hrs. 31 hrs. 47 hrs. 59 hrs. 



Culture Illb 14° 14° 14° 14° 14° 14° 



Culture Illb + IIIx 14° 14° 14° 14° 17° 71° 



Culture IIIx 14° 14° 15° 15° 18° 20° 



The third table will illustrate how the associate influence is felt from the' 

 beginning, and appears to extend throughout the process. 



Time after inoculation. hrs. 24 lirs. 48 his. 07 l»rs. 



Culture Ig 18° 22° 29° 30° 



CultUH! Ig + Ij 18° 33° 39° 4C° 



Culture Ij 18° 23° 2<i° 28° 



RELATION OF THE NUMBER OF ASSOCIATE AND LACTIC MICRO-ORGANISMS, 

 INTRODUCED INTO THE COMBINED CULTURE, TO THE ACCELERA- 

 TION OF THE LACTIC MICRO-ORGANISMS. 



Doubtless the relative number of bacteria introduced into a flask of milk 

 would have a decided influence upon the results of association, provided 

 the associate micro-organisms w^ould develop as rapidly as the lactic in milk. 

 In work of this character much is dependent upon this feature. 



We have not been able to control the number introduced. In all of the 

 work, the only means was to ascertain the number after introduction and 

 accept the results in the light of a weakness of technique. Yet this very 

 weakness, has, in a manner, contributed many sides which would other- 

 wise have been overlooked. 



The annexed table will illustrate the significance of numbers to some ex- 

 tent — constant letters, or the last letter of each combination represents 

 the lactic micro-organisms, while the fh'st letter represents the associate 

 micro-organism. Plus indicates that the lactic micro-organism has been 

 accelerated, minus that it has been retarded, plus-minus that no effect has 

 been noticed. 



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