188 



MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



EXPLANATION OF CHART 3 



Comparison of this record for IMaroh ]Oth with that for the preceding 

 day (chart 2) shows a delay on the 10th of from one to two hours in 

 the clock hour when the firsts started to open. The relative behavior of 

 the varieties, however, remains quite the same. This general shift of 

 opening to later hours was due to the fact that the night preceding the 

 ]Oth was several degrees cooler than were the nights of the 8th and 

 the 9th. 



As here shown, the varieties at the lower end of Class B are most 

 easily thrown into irregular blooming particularly in the opening of a 

 set for the first period. It was almost 6 :00 P. M. when this set started to 

 open on Trapp and evidently this set failed to open on Estelle and Taft's 

 Golden. 



A delay of several hours in the opening of flowers by any variety may 

 thus occur from day to day as a result of slight deviations from previous 

 night tempci-atures. The delay is, however, quite general and uniform 

 throughout, so that the relative behavior of the different varieties remains 

 remarkably the same. 



