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tures but sunny days, sets of flowers frequently remain fully open 

 as long as 60 hours or occasionally as long as J2 hours. Thus 

 a large well-established plant of the Lemon Daylily may have a 

 period of blooming which covers several weeks, and during this 

 entire period at least one set of flowers will be open at any hour 

 of the day or the night. 



Figure 2. Flowers of the Lemon Daylily (Hcmcrocallis fiava). A set 

 of flowers (see 1) may remain open and in good condition for two periods 

 of daylight, and thus overlap a newer set (see 2), which is for a time 

 somewhat paler in color. 



The extended flowering seen in the Lemon Daylily is a com- 

 bination of both the nocturnal and the diurnal habits with also 

 some further extension. Under certain temperatures the sets 

 open in the late afternoon or evening almost as for the strictly 

 nocturnal flowering, but the sets continue open throughout the 

 following day and into the night beyond the hour when the 

 flowers of the limited diurnal habit have fully closed. 



For plants of the species H. minor observations indicate that 

 the general rule is that two sets are open during most of the 

 night, especially from sunset until midnight, and that there is one 

 set open during the hours of daylight. 



