50 MICRO-ORGANISMS AND FERMENTATION. 



appearance later ; as, for instance, after five days. Among 

 the latter growths are those species which develop less 

 readily in wort ; and in the brewery these will therefore 

 be generally suppressed by the yeast, and are consequently 

 of less importance in the examination of water or air. 

 Analyses according to this method have been executed by 

 Holm, Wichmann, and several others. 



For the control of air- and water-filters KoclCs gelatine 

 method is the best. 



