41 6 WILLIAM A. KEENER AND WILLIAM H. TALIAFERRO. 



position 2 in Fig. 6, a. When the flagellate was left a little 

 farther beyond the apex of the growing pseudopodium the 

 streaming movement of the latter changed its course so as to 

 cause the pseudopodium to send a process or secondary pseudo- 

 podium off behind the quiet Chilomonas. This process or second- 

 ary pseudopodium, through a streaming at right angles to the 

 larger one, grew somewhat larger, then its course became oblique 

 and it traveled like a wave posteriorly along the mesial surface 

 of its parent pseudopodium. This wave-like movement of the 

 secondary pseudopodium carried the yet quiet Chilomonas down 

 to the apex of the angle between the two original pseudopodia. 

 Thus the prey was brought into a relatively small space, which 

 through the fusion of the tip of the secondary pseudopodium 

 and a region near the base of one of the original pseudopodia, 

 became a food vacuole (Fig. 6, a, b, c and d}. 



Perhaps the most interesting condition we have seen presented 

 to the ingenuity of the Amceba proteus is to be seen in the following 

 observation. The Amceba proteus was traveling along the line 

 of a large pseudopodium when it came in contact with a quiet 

 Chilomonas paramcecium. At first the Amceba proteus "seemingly 

 did not react but simply pushed the Chilomonas to one side 

 (Fig. 7, 2). At this point, however, the Amceba proteus protruded 

 a small pseudopodium from the apex of the larger one which 

 proceeded around the Chilomonas (Fig. 7, a) . At the same time it 

 threw out a secondary pseudopodium from the body of the larger 

 one some distance below the Chilomonas (Fig. 7, b}. It, however, 

 withdrew this secondary pseudopodium at b and threw out an- 

 other one (Fig. 7, c), closer to the Chilomonas which immediately 

 proceeded to meet the first enclosing pseudopodium, a. 



After the extreme variability of the Amoeba's reactions to food 

 as seen in these observations one is not justified in saying as 

 does Hegner ('10), "This apparent choice of food may be due to 

 the ordinary physical laws of fluids." In the first place as many 

 if not more Chilomonas paramcecia were rejected as were accepted 

 by the Amcebas. Frequently a Chilomonas paramcecium would 

 come in contact with the "anterior end" or side and then remain 

 by the Amoeba without being ingested. If this were a process 

 involving the "ordinary physical laws of fluids" there would 



