AtJTHOR 8 ABSTRACT OF THIS PAPER ISSUED 

 BT THE BIBLIOGRAPHIC SERVICE, JtTNE 12 



THE GROWTH OF PARAMECIUM IN INFUSIONS OF 

 KNOWN BACTERIAL CONTENT^ 



RUTH L. PHILLIPS 



ONE FIGURE 



CONTENTS 



Introduction 135 



Methods 136 



a. Media 136 



h. Reactions of the media 137 



c. Isolation of the bacteria used for feeding Paramecium 138 



d. Characteristics of these bacteria 139 



e. Method used for growing Paramecium in pure cultures of bacteria. 143 

 Observations 148 



a. Growth of Paramecium aurelia in certain pure cultures of bacteria in 



0.1 per cent standard timothy hay infusion 148 



6. Behavior of Paramecium when fed upon pure cultures and mixtures, 



of the bacteria A', B', C, under varying experimental conditions . . 150 



1. Behavior of Paramecium when fed upon pure cultures of bacteria 



A', B', C, and the mixtures, A'B', A'C, B'C, and A'B'C, 

 in 0.1 per cent standard timothy hay infusion from August 28, 

 1920, to March 7, 1921 151 



2. Change of food of Paramecium without change of medium 162 



3. Changing the medium without varying the food 164 



4. Change in medium accompanied by change in food 168 



5. The effect of sterile media 169 



Historical and discussion 170 



Summary 181 



Literature cited 182 



INTRODUCTION 



The work of Hargitt and Fray ('17) on feeding pure lines of 

 Paramecium with pure cultures of bacteria initiated a new phase 

 in the investigation of protozoan metabolism. This work out- 

 lined the methods necessary for such a study and summarized 

 the probable effect of pure cultures of bacteria, or mixtures of 



1 Contributions from the Zoological Laboratory, Liberal Arts College, Syracuse 

 University; C.W. Hargitt, Director. 



135 



