PAPERS OX BIOLOGY AND AGRICULTURE 



195 



this lack of growth to the fact that by the longitudinal 

 cut the vascular bundles were not sufficiently injured, 

 Wakker 3 said that the growth of adventitious buds on B. 

 calycinum could be brought about by injuring or disturb- 

 ing the water passages of the leaf. 



38 



PLATE VII 



Child and Bellamy 4 found that cooling a portion of 

 the petiole of a B. calycinum leaf to a temperature from 

 2.5 to 4° C. for a few days was a very effective means of 

 inducing notch growth. 



