CONTENTS xi 



SECTION PAGE 



5. BACILLUS RADICICOLA - 179 



6. MODE OF ENTRANCE OF BACTERIA INTO LEGUMINOUS PLANTS 181 



7. RELATION OF NITROGEN-BACTERIA TO LEGUMINOUS PLANTS - - 182 



8. INOCULATION OF SOIL WITH BAG. RADICICOLA 183 



CHAPTER XIV. 

 NITRIFICATION AND DENITRIFICATION 



1. NITRIFICATION 185 



2. NITRITE -BACTERIA - 187 



3. VARIETIES OF NITRITE-BACTERIA - 189 



4. PHYSIOLOGICAL CHARACTERISTICS OF NITRITE-BACTERIA 191 



5. NITRATE-BACTERIA 192 



6. MORPHOLOGICAL AND PHYSIOLOGICAL CHARACTERISTICS OF NITRATE- 



BACTERIA - 193 



7. NITRIFICATION IN NATURE 194 



8. ORGANISMS THAT REDUCE NITROGEN COMPOUNDS : DENITRIFICATION 195 



CHAPTER XV. 

 FERMENTATION 



1. INTRODUCTION- - 198 



2. THE NATURE OF YEAST- 199 



3. EXAMPLES OF FERMENTATION 200 



Yeast- fermentation malt fermentation acetic-acid fermentation. 



4. DEFINITION OF FERMENT AND OF FERMENTATION PROPERTIES OF 



FERMENTS - 201 



5. CLASSIFICATION OF FERMENTS - 204 



6. FERMENTATIONS FROM WHICH NO SOLUBLE FERMENTS HAVE BEEN 



EXTRACTED - - .... 206 



Lactic-acid fermentation acetic-acid fermentation butyric-acid 

 fermentation fermentations resulting in transformation of nitro- 

 genous organic compounds, of sulphur compounds, of propionic-, 

 citric-, and oxalic acids. 



