CONTENTS. 



Introduction: Objects of the Investigation, 

 Description of the Movements and Reactions, 

 The Movements, 



The Movements of Amoeba as described 

 by Rhumbler and Butschli ; Agree- 

 ment with Currents in a Drop of 

 Fluid Moving as a Result of a Local 



Decrease in Surface Tension 133 



Currents in Amoeba as studied from above; 



Lack of Backward Currents 134 



Movements of Upper and Lower Surfaces 

 Studied Experimentally ; Rolling 



Movement 138 



Antceba verrucosa and Its Relatives. 140 



Other Species of Amoeba 146 



Historical on Rolling Movements in 

 Amoeba 148 



132 

 132 



Formation and Retraction of Pseudopodia 

 Surface Currents in Formation of 

 Pseudopodia in contact with Sub- 

 stratum 



Formation of P'ree Pseudopodia 



Withdrawal of Pseudopodia 



Movements at Anterior Edge 



Movements of Posterior Part of Body 



General View of Movements of Amoeba in 



Locomotion 



Some Characteristics of the Substance of 



Amoeba 



Fluidity 



Rhumbler's Ento-ectoplasm Process 



Elasticity of Form in Amceba 



Contractility in Ectosarc of Amoeba. 



iSa 



152 

 153 

 IS6 

 160 

 165 



169 



173 

 173 

 173 

 '75 

 177 



Reactions to Stimuli, 



Reactions to Mechanical Stimuli 181 



Positive Reaction 181 



Negative Reaction 182 



Reaction to Chemical Stimuli 187 



Reaction to Heat 190 



Reactions to Other Simple Stimuli 191 



181 



Some Complex Activities 



Activities connected withFood-taking 



Taking Food - 



Pursuit of Food 



Other AmcebsB as Food 



Reactions to Injuries 



193 

 193 

 193 

 196 



Physical Theories and Physical Imitations of Amoeboid Movements, 



204 



Surface Tension Theory 204 



Berthold's Theory that One-sided Adher- 

 ence to Substratum is the Cause of 



Locomotion 208 



Experimental Imitation of Locomo- 

 tion in Amceba 209 



Formation of Free Pseudopodia 214 



Behavior of Amoeba from Standpoint 

 Behavior 



Habits in Amceba 826 



Classes cf Stimuli to which Amoeba Re- 

 acts 927 



Types of Reaction 227 



Summary, 



Experimental Imitation of Movements 

 due to Local Contractions of Ectosarc 

 and of the Roughening of Ectosarc in 

 Contraction 215 



Direct or Indirect Action of External 

 Agents in Modifying Movements 219 



Direct or Indirect Action in Food-taking, 222 



General Conclusion 225 



of Comparative Study of Animal 



226 



Relation of Different Reactions to Differ- 

 ent Stimuli; Adaptation in Beha- 

 vior of Amoeba 327 



Reflexes and "Automatic Actions" in 



Amoeba 23S 



Variability and Modifiability of Reactions 229 



230 



130 



