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LIBBIE H. HYMAN 



variably, but certainly in the vast majority of cases. If the 

 needle point is pressed against the anterior end, then the new 

 pseudopodia appear at the posterior end ; if applied at the poste- 

 rior end, the anterior end first contracts, then resumes its ad- 

 vance, hastening its movement; if to one side, the opposite side, 

 or the most distant end advances, and so on. I should state 

 that I refer to the pseudopodia which appear first after the 

 stimulation for these may not be the ones with which the animal 



Figs. 9 to 11 Avoiding reaction of amoeba to strong mechanical stimulation. 

 Figure 9a, stimulus applied to posterior end of an advancing amoeba; b, the 

 anterior end contracts, and c, flows forward again. 



Fig. 10a, stimulus applied to side of the amoeba; b, anterior end contracts; 

 c, subsequent locomotion to side opposite that to which stimulus was applied. 

 11a, stimulus applied near anterior end; 6, anterior end contracts; c, pseudopodia 

 initiated at posterior end. 



