324 CHAP. XXIX. GEO-ELECTRIC RESPONSE OF THE SHOOT 



the specimen is rotated on its long axis, the vertical com- 

 ponent of the force of gravity increases with the angle of 

 inclination. The hypothetical statolithic particles will 

 become displaced all along the cells, and the vertical 

 pressure exerted by them will also increase with the angle. 

 Experiment 179. — The specimen was rotated through 

 45° and the maximum electric response observed. The 

 angle was next increased to 90° and the reading for the 

 enhanced response taken. The ratio of the geo-electric 

 response at 90° and 45° thus affords a measure of the 

 effective stimulation at the two angles. I give below a 

 table of the results obtained with twenty-four different 

 specimens. 



Table XX. 



-Relation between Angle of Inclination and 

 Geotropic Excitation. 



