50 P. G. HEINEMAN AND CHARLES R. HIXSON 



beyond the second phase of fermentation. According to the 

 investigation reported in this paper the third phase of fermenta- 

 tion, when lactobacilU are active, does not occur during the 

 first weeks of the ripening process. 



The investigation came to a conclusion because the silage was 

 practically exhausted in the silos whose product was available. 

 The remaining 'silage contained considerable quantity of acid 

 and the owners of the silos hesitated to use this remnant for 

 foddei'. It does not seem, however, that the acidity was great 

 enough to cause injury to the cattle. Fair samples could not be 

 obtained from these remnants. 



It has been stated that stains from early samples of silage 

 showed the presence of large numbers of microorganisms of 

 various types. During the progress of the work the number of 

 types was gradually reduced and the microscopic picture of 

 stains from the last stages of ripening differed materiall}^ from 

 that obtained from early stages, inasmuch as streptococci and 

 lactobacilli were clearly predominant and other forms had dis- 

 appeared in very large measure. No doubt the result is explained 

 by the accumulation of acid in the final product. The disap- 

 pearing bacteria may influence the ripening process by consum- 

 ing oxygen and thus create favorable conditions for facultative 

 anaerobes, such as streptococci and lactobacilli. 



CONCLUSION 



The authors as a result of this in\'estigation offer as a tenta- 

 tive hypothesis of the ripening process of corn silage the follow- 

 ing: The fermentation consists of three phases brought about 

 by three groups of bacteria. The initial phase is of short dura- 

 tion and is caused by members of the colon-aerogenes group of 

 bacteria. It is accompanied by acid and gas formation. The 

 second phase is carried on by streptococci and is accompanied 

 by moderate acid formation. The third phase is the result of 

 the activity of lactobacilli. The third phase may possiblj^ be 

 subdivided into minor phases owing to the presence of different 

 strains of lactobacilli. It should he added that the assumption 



