XIV TABLE OF CONTENTS 



PAGE 



Sulphur bacteria .......... 1 86 



Iron bacteria 



CHAPTER XVII 

 THE CHROMOGENIC BACTERIA 



Introduction ........... lo, o 



Range of color ........... 190 



Location of pigments ......... 191 



Solubility ........... 194 



Historical allusions .......... 196 



CHAPTER XVIII 

 THE PHOTOGENIC BACTERIA 



Introduction ........... 198 



Distribution ........... 198 



Food requirements .......... 199 



Oxygen requirements ......... 200 



Temperature requirements ........ 200 



Methods of isolation ......... 201 



Pathogenesis ........... 2OI 



CHAPTER XIX 



THE ZYMOGENIC BACTERIA 



Introduction . . .......... 202 



Organized and unorganized ferments ...... 204 



Lactic acid fermentation ......... 206 



Acetic acid fermentation ......... 208 



Butyric acid fermentation ......... 209 



Methane fermentation ......... 21 1 



Higher alcohols, aromatics, and fatty acids ..... 211 



Bacterial fermentations in the arts ....... 214 



CHAPTER XX 



THE SAPROGENIC AND SAPROPHILIC BACTERIA 



Introduction ...... ... . . . 216 



Proteolytic enzymes ..... . . . . . 217 



