LEAF EXPOSURE TO SUN AND AIR 149 



revolving table before a window and slowly turned during 

 the hours of daylight? 



158, Review Summary of Chapter X. 



f For vertical twigs . . . 

 Leal arrangement ... < _ . . 1 , J . 



L For horizontal twigs . . . 



f Apparatus for 



Movements of leaves . . -I Causes of 



[ Uses of 



Compass-plants .... 



( Positive . 



Heliotropic bending of stems ^ _ 



I Negative . 



