PHYSIOLOGY 



85 



cumvallation," in which the amoeba without contact with the 

 food, forms pseuclopodia which surround the food on all sides and 

 ingest it (c); 4) by "invagination," in which the amoeba touches 

 and adheres to the food, and the ectoplasm in contact with it is 



Fig. 32. Various waj's by which amoebae capture food organisms. 



a, Amoeba verrucosa feeding on Oscillatoria by 'import' (Rhumbler); 



b, A. proteus feeding on bacterial glea by 'circumfluence'; c, on Para- 

 mecium by 'circumvollation' (Kepner and Whitlock); d-h, A. ver- 

 rucosa ingesting a food particle by 'invagination' (Gross- Allermann). 



invaginated into the endoplasm as a tube, the cytoplasmic mem- 

 brane later liquefies and disappears {d-h). Jennings, Kepner, 

 Schaeffer and others, have made studies with reference to the 

 food-ingestion in amoebae. 



In certain testaceans, such as Gromia, several rhizopodia co- 

 operate in engulfing the prey and, in Lieberkuhnia (Fig. 33), Ver- 

 worn noted cihates are captured and digested in the rhizopodium. 



