THE FLOWER BEHAVIOR OF AVOCADOS 



153 



The iiiunber of varieties liaving the A behavior is nearly 

 equal to the number having B behavior. There is no definite 

 evidence regarding the heredity of flower behavior further than 

 the fact that the two main classes A and B seem to exist in nearly 

 equal numbers. 



The cycles or dianthesis of the sets of flowers 



The entire time from the first opening to the final closing of a 

 flower or of sets of flowers, Avhich includes the two periods of 

 opening and the interval of closing between them, may be called 

 the comj^lete cycle of dianthesis, the flowering cycle, or merely 

 "the cycle" of a flower or of a set of flowers. 



The striking difference in the dailij behavior of the flowers of 

 the two main classes of avocados is that the sequence of the two 

 sets is reversed. This involves and is accomplished by decided 

 differences in the flowering cycle of the sets of flowers with ref- 

 erence to the time of the day when the two periods of anthesis 

 occur and in respect to the length and the time of the interval 

 during which the flowers are closed between the two separate 

 openings. This is revealed by "tagging" some of the flowers 

 and tracing their behavior throughout the following day. This 

 method was used very generally throughout the investigations 

 both in California and in Florida. 



The main types of flowering cycles thus revealed for sets of 

 flowers may be shown by the diagrams in chart 5. 



For the A varieties (of which Taylor, described above, is 

 typical) daily a set of flowers opens for the first or female open- 

 ing in the forenoon and then closes about noon to remain closed 

 for 24 hours (until the folloAving afternoon) before opening for 

 the second or male opening. The cycle of a set covers about 36 

 hours. During the hours of sunlight each day two different sets 

 of flowers are in action. During the hours of darkness one set 

 is in the interval between the two openings (see A in chart 5). 



For all B varieties, in normal behavior, daily a set of flowers 

 opens for the first or female opening in the afternoon and closes 

 late in the afternoon. But in respect to the further history of 

 the sets, there is a decided diversity. 



