CONTENTS 



XV 



XXXI. THE FERMENTATION OF CHEESE, AND ALLIED 

 DECOMPOSITIONS. 



175. The Composition of Ripe Cheese 243 

 Con version of Albumen into Fat 244 



176. Duclaux' Studies on Cantal 



Cheese 244 



177. Changes in the Bacterial Flora 

 of Ripening Cheese Aromatic 

 Cheese 245 



178. Pure Culture Ferments . . 246 



179. Natto and Mi so . 



180. The Normal Pitting of Cheese . 



181. The Cause of Puffy (" Blown ") 



Cheese 



182. Cheese-makers' Recipes 



183. Counteracting Puffiness in 



Cheese 



184. Bitter Milk and Bitter Cheese . 



PAOK 



247 

 248 



2 49 

 250 



2.51 

 251 



CHAPTER XXXII. THE FERMENTATION OF UREA, URIC ACID, AND 

 HIPPURIC ACID. 



185. Urea, the Final Product of 



Animal Metabolism . . . 253 



1 86. Urea Unassimilable by Higher , 



Plants 254 



187. Discovery of the Urea-Ferment 



by Pasteur . . . 254 



1 88. Researches of P. Miquel . . 255 



189. Urase 257 



190. The Decomposition of Uric Acid 



and Hippuric Acid . . . 257 



CHAPTER XXXIII. THE FIXATION OF FREE NITROGEN BY BACTERIA. 



191. Accumulators and Consumers of 



Nitrogen 259 



192. Discovery of the Leguminous 



Nodules 261 



193. Formation and Functions of the 



Nodules . , 262 



194. The Nodule Bacteria . 



264 



195. The Bacteroids Infection 



Thread 266 



196. Clostridium Pasteurianum . 



269 



Section IX. Oxidising Fermentations. 

 CHAPTER XXXIV. THE IRON BACTERIA. 



197. Morphology of the Genera 



Crenothrix and Cladothrix . 272 



198. Physiology of the Iron Bacteria 



Smell of the Soil . . . 275 



CHAPTER XXXV. THE SULPHUR BACTERIA. 



199. Morphology of the Genus Beg- 

 giatoa Artificial Cultivation 

 < cverr of the Sulphur Bacteria . . 278 

 200. The Species of the Genus Thio- 



thrix 280 



201. Morphology of the Non-Fila- 

 mentous Sulphur Bacteria 

 Bacterio-p.i;rpurin . 



281 



202. Physiology of the Sulphur Bac- 

 teria The Limanes . . 283 



CHAPTER XXXVI. THE NITRIFYING BACTERIA. 



203. The Recognition of Nitrification 



as a Physiological Process . 288 



204. Nitroso-Bacteria and Nitro-Bac- 



teria 289 



205. Nitrosomonas and Nitroso- 



coccus 290 



206. The Nitro-Bacteria . . .291 

 207. Assimilation in the Dark . . 292 

 208. Wall-Saltpetre and Plantation- 

 Saltpetre . . . 293 



