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AMEBOID MOVEMENT 



Figure 33. Illustrating the path of an Amoeba bigemma under con- 

 trolled conditions, in ordinary diffuse light from a north window. For 

 convenience of reference the waves in the path are numbered from i to 

 23. The figures were drawn with the aid of a camera lucida at intervals 

 of one minute. The path was recorded from 8 :s8 to 10 -.26, when fission 

 occurred. After fission, the path of one of the daughter cells was fol- 

 lowed for a short time, but the ingestion of a mass of debris destroyed 

 the regularity of the path. The vertical lines at the point where fission 

 occurred indicate that the figures above the lines were moved up the 

 length of the lines. The first figure beyond wave 13 was influenced in its 

 movements by a mass of debris lying to its left. Average length of the 

 ameba, 150 microns. 



