TABLE OF CONTENTS. XI 



CHAPTER XIV. 



UNICELLULAR PLANTS. 



A. PROTOCOCCUS. 



PAGB 



General account. Habitat. Morphology. Structure. Motile and non- 

 motile states. Reproduction by fission. Cell-aggregates. Physi- 

 ology. Income and outgo. The making of starch from inorganic 

 matters. The fundamental physiological properties of protoplasm as 

 displayed by plants Comparison of Protococcus with Amoeba, and 

 chlorophyll-bearing plants in general with animals in general. Other 

 unicellular chlorophyll-bearing plants: diatoms; desinids; Chroococ- 

 cus; Glceocapsa; etc 178 



CHAPTER XV. 



UNICELLULAR PLANTS (Continued). 

 B. YEAST. 



General account. Wild yeast and domesticated yeast. Microscopical 

 examination of a yeast-cake. Morphology of the yeast cell. Cyto- 

 plasm and nucleus. Reproduction by budding and by spores. Physi- 

 ology. Yeast and the environment. Dried yeast. Income. Meta- 

 bolism. Outgo. The minimal nutrients of yeast compared with 

 those of Protococcus and Amoeba. Why yeast is regarded as a plant. 

 Top yeast Bottom yeast. Wild yeasts. Red yeast. Fermentation 

 and ferments. Unicellular plants not necessarily at the bottom of 

 the scale of life; etc 184 



CHAPTER XVI. 



UNICELLULAR PLANTS (Continued). 

 C. BACTERIA. 



The smallest, most numerous, and most ubiquitous of known living 

 things. Their abundance in earth, air, milk, water, etc. Comparison 

 of their work in soils with that of earthworms. Parasitic and sapro- 

 phytic bacteria. Their botanical position. Sanitary and economic 

 importance. Morphology. Structure. Cytoplasm and nucleus. 

 Cilia. Their size. Swarming and the resting stages. Reproduction. 

 Endospores. Arthrospores. Physiology. Income. Metabolism. 

 Outgo. Ferments. Fermentation. Putrefaction. Disease. One 

 species capable of living upon inorganic matter. Related forms. 

 Why bacteria are regarded as plants. The relations of bacteria to 

 temperature, moisture, poisons, etc. Sterilization, Pasteurizing, 

 disinfection, filtration, etc 192 



