A. R. SCHRANK 



137 



MILLIVOLTS 



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MILLIMETERS Curvature 



'' I I I *''''*' I 



50 MINUTES 100 



Figure 7. A. Electrical responses oi Avena coleoptiles to 10 microamperes 

 of direct current applied longitudinally for 2 minutes to a 5 millimeter apical 

 segment. Each curve is an average of 5 or more experiments. B. Correspondmg 

 average curvatures plotted as millimeters of horizontal tip movement. 

 Numerals at the right of the curves show the average angular curvatures at 

 the end of the experiments. 



