CONTENTS Vll 
E. Moisture and Desiccation 39 
F. Oxygen: Aerobiosis and Anacrobiosis .... 40 
G. Temperature 40 
1. General 40 
2. Cold 41 
3. Heat 42 
Dry Heat, Moist Heat 43 
H. Heat Production 43 
I. Light and Electricity 43 
Electricity 44 
J. Gravity, Osmotic Pressure, Agitation, Chemotaxis 44 
1. Gravity 44 
Diminished Pressure 45 
2. Osmotic Pressure 45 
3. Agitation 46 
4. Chemotaxis 47 
K. Enzymes, Toxins, Ptomains 47 
Enzymes 47 
Exo-enzymes 47 
Endo-enzymes 48 
Classification of Enzymes 48 
Ptomains 50 
L. Pigments 51 
M. Symbiosis, Antibiosis and Commensalism 51 
N. Media— Composition and Reaction 52 
O. Growth of Bacteria in the Animal Body 53 
CHAPTER HI. 
The Chemistry op Bacteria. The Effect of Bacteria on Their 
Environment. 
A. General Chemistry of Bacteria 54 
B. Chemical Composition of Bacteria 56 
1. Elementary Composition 56 
2. Chemical Constitution 56 
3. Chemical Composition of Bacteria 57 
C. Composition of the Morphological Components of the Bacterial Cell 59 
1. Cell Membrane 59 
2. Capsule 60 
3. Cytoplasm 60 
Carbohydrates 61 
Fat and Fatty Derivatives 61 
Inorganic Constituents 62 
4. Spores 62 
D. Food Relationships of Bacteria 63 
1. General 63 
2. Sources of Food 63 
Nitrogen 63 
Carbon 64 
Hydrogen 64 
Oxygen 64 
Inorganic Salts 64 
CHAPTER IV. 
Bacterial Metabolism. 
I. General Bacterial Metabolism 66 
II. The Nature of Bacterial MetaboUsm 68 
III. Nitrogen MetaboUsm 69 
IV. Carbon Metabolism 70 
41989 
