72 MYSTERIES OF THE FLOWERS 



The first night the opposite stamens shed their 

 pollen, and for a few hours the flower is fragrant, 

 attracting the night-moths. 



The second night the petals open again, the 

 fragrance has come again, and the alternate stamens 

 are offering their pollen. 



The third night, when the petals roll back for 

 the last time, all the anthers have fallen, the fila- 

 ments curl back, leaving the way clear for the open 

 stigma to advance and receive the magic touch of 

 the moth. 



It is probable that the lure of fragrance thrice 

 renewed is accompanied by nectar rising in three 

 succeeding tides. 



In the Umhellifei'ce — such as the Angelica — the 

 honey is exposed in open, saucer-shaped cups, where 

 it can be obtained readily by throngs of short- 

 tongued insects. In a whole head all the stigmas 

 develop after all the pollen has been shed; thus the 

 whole flower-head changes from the staminate to 

 the pistillate condition. Accordingly, whatever 

 pollen is received by the pistils must come from 

 another flower-head, and not from an adjoining 

 floret, thus obtaining a wider range of cross-fertili- 

 sation with all the attendant advantages. 



