THE ROLE OF THE INHIBITING EFFECT 



63 



Fig. 49. — Stem suspended in water with the exception of the apex. Roots 

 now permanent in all the nodes in water. Polarity as regards root formation 

 disappears. Oct. 12, 1920 to Jan. 4, 1921. 



In water 



Fig. 50. Fig. 51, 



Fig. 50. — When stems are put with their apices into water, all the nodes can 

 form shoots. Polarity disappears. Oct. 7 to 30, 1919. 



Fig. 51.^ — Stems suspended simultaneously in air form shoots only at apex. 

 Oct. 7 to 30, 1919. 



