372 FOUNDATIONS OF BOTANY 



440. Protection of Pollen from Rain. Pollen is very 

 generally protected from being soaked and spoiled by rain 

 or dew either by the natural position of the flower prevent- 

 ing rain from entering, as in the case with most gamo- 

 petalous, nodding flowers, or by changes in the position 

 of the flower, and by its opening in sunny weather and 

 closing at night or during rain. Sometimes the flower 

 both changes its position and closes, as is the case with 

 the herb Robert and the sweet scabious (Fig. 262). The 

 adaptations of flowers to protect their pollen from becom- 

 ing wet can best be understood by actually examining the 

 same flower in sunshine and during rain. 



