REPRODUCTIVE ORGANS 



115 



Fig. 115. A winged seed of Bignonia— After Strasbcrger. 



spores called pollen 

 and occasionally 

 falling upon the 

 right spot for 

 germination . 

 With such an 

 agent of transfer 

 the pollen must 

 he very light and 

 powdery, and 

 also very abun- 

 dant, for it must 

 come down al- 

 most like rain to be 



grains being scattered by the wind, 



Fig. 117. 



Winged fruit of 

 Kerxer. 

 9 



Fig. 116. Winged fruit of maple.— After Kzrxer. 



certain of reaching the right places. 

 Among the gymno- 

 sperms (pines, hem- 

 locks, etc.) this is the 

 exclusive method of 

 pollination, and when a 

 pine forest is shedding 

 pollen the air is full of 

 the spores, which may 

 be carried to a great 

 distance before being 

 deposited. Occasional 



Ptelea.— After 



