148 



MEMOIRS or THE Is^EW YORK BOTANICAL GARDEN 



is frequently dark colored and sometimes it is shriveled and 

 dead. The outer set of six stamens stand at an angle of about 

 45°. Xot long after these flowers are open, pollen begins to be 

 shed. 



The pollen is ingeniously lifted out of each of the four cham- 

 bers of an anther by a spoon-shaped valve that opens quite lilve a 

 trap door and bends upward. A somewhat sticky mass of pollen 

 is gently held within the infolded margin of each valve, some- 

 what as one might hold a ball of popcorn in an uj^raised hand. 

 Thus the nine rod-shaped stamens of each flower stand bristling 

 in different directions with pollen exposed in several directions 

 from their summits (see 4 in plates 25 and 26). Below at the 

 base of the outer set of stamens and between the stamens, a set 

 of short-stemmed dome-shajjed nectaries excrete thick films of 

 nectar. In their efforts to obtain this nectar bees and other in- 

 sects climb over the stamens, push in between them and their 

 hairy bodies become more or less smeared with the sticky pollen. 

 But if pollen is not carried away by insects the sticky substance 

 about and between the grains hardens and l)inds the pollen 

 grains of each valve into a dry caked mass wliich then soon falls 

 to the ground. 



A careful census of the many flowers oj)en on the Taylor tree 

 during the afternoon will reveal that they are all in the same con- 

 dition. They all shed pollen, the maximum of shedding being 

 some time during the afternoon. Late in the afternoon these 

 flowers close never to open again. 



Thus, during the hours of daylight of a single day, two dif- 

 ferent sets of flowers open and close on a tree of the Taylor 

 variety. The flowers which are ojDen during the forenoon func- 

 tion only as females, those open during the afternoon function 

 as males. 



The differences in these two sets of flowers, and their rela- 

 tions to each other, become clear when the normal life-history or 

 cycle of a single set is traced. The set which is open during the 

 forenoon closes around midday and remains closed during that 

 afternoon, the night following, and the next forenoon. In normal 

 flower-beliavior a set of flowers is open for the first or female 

 opening during the forenoon of each day and is open for the 



