of a paktial removal of koots, etc. 5 



Experimental Data. 



I. Removal of root. 



(1) Pharbitis hederacea. 



As culture fluid, Sachs' solution was used and renewed 

 once every week. 



The water-cultures were arranged in three series. In the 

 first series, the main root and a few lateral roots w-ere removed 

 once every day, leaving three lateral roots untouched. In the 

 second series, they were removed once every three days and the 

 third series served as the control. 



As the following table shows, the first series flowered first 

 and the flowers were normal. 



In the third series, the vegetative parts grew very well, the 

 leaves being about twice as large as those of the first series. 



Many flowers of the third series were abnormal and small. 

 The second series lay between these two extremes. 



The size of flower given is that of the one which opened 

 first. 



