KENTIA PALM 233 



to the vertical. After a time it became curved upwards 

 under the stimulus of gravity, and showed a very marked 

 up and down movement similar to that of the Faridpore 



Fig. 136. The Diurnal Indicator. 



Movement up and down of tree indicated by anti-clock\\'ise or 

 clockwise movement of index on the circular scale (Kentia). 

 {See text.) 



Palm. The apparatus described below made it easy to 

 demonstrate the periodic diurnal movement. 



The Diurnal Indicator.— A small wheel is adequately 

 supported in a fork not shown in the figure. The upper end 

 of a string S is attached to the Palm where it curves up, 



