198 



MEMOmS OF THE >^EW YORK BOTANICAL GARDEN 



EXPLAXATIOX OF CHART 8 



These records obtained in California illustrate how the flower be- 

 havior of a single tree may vary from day to day in response to weather 

 conditions. 



On May 5th, the daily alteniation and sequence of the two sets of 

 flowei^s were quite noiinal for all six varieties. 



The day of 3Iay 17th was preceded by cloudy weather with some rain 

 and with lower than usual temperatures. Jhe day was cool and mo.stly 

 cloudy. The daily sequence for the three A varieties was the reverse 

 of the normal. For them, in the forenoon, second-period fl.owei's delayed 

 from the previous afternoon were open and in the afternoon fii"st-period 

 flowers delayed from that forenoon were open. For each of the B varie- 

 ties second-period flowere opened in the morning as is normal for this 

 group but they remained open all day. .shedding pollen poorly. Only 

 flowere of this set opened on Linda but for Queen and Panchoy a set 

 of first-period flowers delayed from the previous afternoon were open all 

 forenoon. 



Inclement weather continued until the early forenoon of the 19th 

 when the clouds cleared and the temperatures rose decidedly. On this 

 day each of the three A varieties had three sets open ; (1) a set of second- 

 period in the forenoon continued or delayed from the previous day; (2) 

 a set of fii*st-period flowers delayed from that forenoon, and (3) a set 

 of second-period flowei-s delayed for that afternoon. Of the B varieties, 

 Queen and Panchoy had only one set of flowers which had probably 

 skipped a previous opening. But Queen had three sets in nearly the 

 reveree sequence of the three sets of opening on the A varieties that day. 



