214 



BOTANICAL GAZETTE 



[march 



gained, however, by comparing the average growth intensities for 

 different periods in the growing season. It follows that the shorter 

 the intervening time periods, the greater would be the vacillations 

 in the data. With this idea in view table F was constructed. 

 It includes figures of growth intensity from tree I during the summer 

 of 1 9 13. The width in microns of the new growth is given for 6 

 different periods, together with the total increase from period to 

 period and the average gain per day. The last will give, not the 

 actual, but the average intensity of growth of the period just 

 preceding. 



If the data of April 26 and May 12 are compared, the following 

 points are to be observed. The average growth intensity was 

 greatest in cutting II, with cuttings I, III, and IV following in the 

 order named. On June 12, 31 days later, cutting IV exhibited the 

 greatest average growth intensity, with cuttings III, I, and II 

 following in the order named. Again, in the cuttings of August 18 

 and September 19, different combinations occur. At the first 

 named date, growth was more rapid in cutting II, while at the 

 latter date it was in cutting IV. 



TABLE F 

 Growth amount and intensity, tree 1; season 1913 



