ON THE FEEDING HABITS OF AMEBA^ 



ASA A. SCHAEFFER 



University of Tennessee 



SIX PLATES 



CONTENTS 



Introduction 530 



Material 533 



The Amebas 533 



The granular type 533 



The raptorial type 534 



Methods 536 



General description of the feeding process 539 



Character and formation of food cups 543 



Size of food cups 545 



Number of food cups 546 



Modifications in the formation of food cups 546 



The food vacuole 549 



Experimental results 550 



Reactions to whole organisms and to parts of organisms 550 



Reactions to moving organisms 552 



Reactions to dead and to motionless organisms and to parts of organisms 553 



Reactions to very slightly soluble substances 555 



Carmine 555 



India ink 570 



Uric acid 571 



Solid egg white 572 



Summary 574 



Bibliography 575 



Explanation of plates and table of abbreviations 577 



' The spelling of ameba was adopted after some deliberation; it is not used as 

 a substitute for the word Amoeba of scientific nomenclature, as has been done in- 

 advisably, to my mind, by some writers; but it is used as a common name in the 

 same way that the Germans employ Amoba, the French amibe, and the Italians 

 ameba, as common names. 



529 



