C'07?.V STRrCTVEE 



89 



CUTKP 



Fig. 36. — Diagram showing Course of the Pollex-tube through 

 Silk to Ovary. 



A, section near outer end of silk, showing pollen-grain and pollen-tube ; 



B, section through base of silk and through young grain. (Drawing by 



C. S. Ridgway.; 



The pollination of corn is effected almost entirel}^ by 

 the wind, which may carry the pollen great distances. 



