SUMMARY OF CONTENTS ix 



3. Katabolism in Autotrophic and Heterotrophic Plants 



a. Respiration. Decrease in dry weight, 1 1 ; economic coefficient, 191. Extent of 



respiration. Proof, i g i ; respiration in chlorophyll-containing cells, 1 94. Res- 

 piratory materials. Carbohydrates: complete combustion, 196; formation of 

 acids, especially in Fungi and succulents, 197 ; fats, 199; proteid, 200. De- 

 pendence on external factors. Light and temperature, 201 ; influence of 

 materials, 201 . Intra-molecular respiration, 202 ; cause (204) and significance 

 (205) of respiration. Historical data, 205. 



b. Fermentation, 207. 



1 . Alcohohc fermentation, especially of yeast, 207 ; nutritive materials, 208 : 



fermentative materials of yeast, 208 ; products of fermentation, 210 ; cause 

 of fermentation, 211; zymase, 211; relation to enzymes, 211; zymase in 

 intra-molecular respiration, 212. Dependence on oxygen, 212 ; aerobes, 

 anaerobes, 213. Biological significance of fermentation, 213. 



2. Butyric acid fermentation, 214 ; effect of oxygen, 215. 



3. Further fermentation of alcohol into acetic and carbonic acids, 216. 



4. Fermentation of carbohydrates, 2 17 ; formation of lactic acid, 2 17 ; formation 



of butyric acid, 217; fermentation of cellulose, 217; fermentation of pectin, 

 218. Conversion of the products of fermentation by other organisms, 218. 



5. Fermentation of proteids, 219. 



4. Special Cases of Anabolism and Katabolism 

 a. Oxidation of inorganic materials (respiration). 



1. Sulphur-bacteria. Beggiatoa. Origin of sulphuretted hydrogen, 2 2 1 ; oxida- 



tion of sulphuretted hydrogen, 221 ; red sulphur bacteria, 223. 



2. Iron-bacteria, 224. 



3. Nitro-bacteiia. Origin of ammonia. Fermentation of urea, 224 ; oxidation 



of ammonia, 225 ; nitrate and nitrite bacteria, 226. 



6. Assimilation in nitro- and sulphur-bacteria. Assimilation of carbonic acid 

 by nitro-bacteria, 227 ; oxidation of organic substances by nitro-bacteria, 228 ; 

 assimilation in sulphur-bacteria, 229; sensitivity of nitro-bacteria to organic 

 substances, 229. 



c. Denitrification and fixation of nitrogen, 231. 



1. Denitrification, 231. 



2. Fixation of nitrogen, 232. Clostridium pasteurianum, 233 ; symbiotic union 



with other bacteria, 233 ; cultures, 234 ; other micro-organisms alleged to 

 fix nitrogen, 234 ; Leguminosae, 235 ; symbiosis with B. radicicola, 237; 

 fixation of nitrogen, 237. 



d. Symbiosis and metabiosis. 



1. Instances related to the case of Leguminosae, 239. 



2. Mycorhiza. Endotrophic forms, 240; ectotrophic forms, 241. 



3. Lichens, 242. 



4. Metabiosis. Circulation of carbon and nitrogen in organisms, 243. 



PART II 



METAMORPHOSIS 



I. Problems of Developmental Physiology 



1. First example : development of the Myxomycetes, 247. 



2. Second example : development of Basidiobolus, 248. 



3. Third example : flowering plants. Development, 250 ; differentiation and division 



of labour, 250; correlations, 252. Influence of external conditions on develop- 

 ment, 252; formal conditions, 253 ; formative results, 254, 



4. Fundamental problems of Biology-. Mechanical explanation of life, 254 ; organi- 



zation and mechanism, 254 ; matter and form, 256. 



