Feeding Habits of Ameba. 59 



Contributions on tKe Feeding Habits 

 of Ameba 



By Asa A. Schaeffer, University of Tennessee. 



Last spring I reported before this Academy the results of some 

 experiments on the feeding- behavior of ameba. I reported then 

 that the abihty to discriminate in feeding resided in ameba, and 

 also that ameba is able to sense insoluble objects, such as glass, 

 at a distance. Since our meeting in April I have obtained addi- 

 tional evidence on these two points, all of which is confirmatory, 

 and I have also obtained some experimental data which extend our 

 knowledge of the feeding habits of ameba in various directions. 

 I wish now to speak briefly of these findings. 



Since reporting on the presence of the power to discriminate 

 in food in ameba at bur last meeting, I have tried a number of 

 additional substances, some of which are eaten, others not. Be- 

 low is a table which presents the results in compact form : 



TABLE I. — The Behavior of Ameba Toward Various Test 

 Substances. 

 Substances Eaten. Substa)iccs Refused. 



Many sorts of one-celled organisms. Arrowroot Starch. 



Aleuronat. Carbon. 



Ameba fragments. **Casein. 

 *Carmine. Cholesterin. 



Crab Meat. Cobalt. 



Egg White. Corn Starch. 



Fibrin (Blood). Cotton. 



Globulin (Egg). *H=Egg Yolk. 



Globulin (Eye). **Gelatin. 



Grain Gluten. Graphite. 



*India Ink. Hematin. 



Keratin. Indigotin. 



* Valueless as food; ** Of food value. 



