CONTENTS. 



INTRODUCTION. 



PAGES 



The Refraction of Light and the Microscope 17-27 



THE REFRACTION OF LIGHT : The Two Fundamental Laws of 



Kefraction ; The Principles of Refraction by Lenses . . . 17-19 

 THE MICEOSCOPE: The Simple Microscope; The Compound 

 Microscope; The Lenses and Lens-systems of the Micro- 

 scope; The Care of the Microscope . . . . 19-27 



CHAPTEE I. 



The Fundamental Principles 27-41 



THE HISTORY OF BACTERIOLOGY 27-28 



THE CLASSIFICATION OF COHN FOR BACTERIA , 28 



THE DEFINITION OF BACTERIA . 28-29 



THE MORPHOLOGICAL CLASSIFICATION OF BACTERIA: The 



Coccus ; The Bacillus ; The Spirillum 29-31 



THE SIZE OF BACTERIA 31 



THE REPRODUCTION OF BACTERIA: Fission; Sporulation . . 32-34 



THE MOTILITY OF BACTERIA 35 



THE RELATION OF OXYGEN TO BACTERIAL LIFE 36 



THE RELATION OF DEAD AND LIVING ORGANIC MATTER TO 



BACTERIA 36 



THE ESSENTIAL CONDITIONS OF BACTERIAL GROWTH : Heat ; 

 Moisture ; Decomposable Organic Material ; Special Chemi- 

 cal Reaction of the Culture-medium . 36-38 



THE INERT AND INHIBITIVE CONDITIONS OF BACTERIAL LIFE 38 



THE VITAL MANIFESTATIONS OR FUNCTIONS OF BACTERIA . 38-41 



