40 



FIELD CROP PRODUCTION 



position to pollinate those higher 

 up. Thus the female flowers 

 on the upper tassel were in- 

 completely fertilized, if .fertilized 

 at all, and due to the loss of 

 function gradually disappeared, 

 so that after a time only male 

 flowers were produced. On the 

 tassels of the lower branches, 

 the male or pollen producing 

 flowers gradually lost their use- 

 fulness, and after a time only 

 female flowers were produced 

 on these branches. 



After the disappearance of the 

 male flowers from the lower 

 branches, the central spike of 

 each tassel developed into what 

 is now the cob, and at the same 

 time the lateral branches grad- 

 ually disappeared. Some proof 

 of this assumption is to be found 

 in the frequent occurrence of an 

 ear developed in the usual way, 

 but with five or six small ears 

 clustered at the base. The small 

 ears are probably due to the 

 reappearance of the lateral 

 branches of the original tassel. 

 After the development of the 

 central spike of the tassel into 

 the ear, the load carried at the 

 end of the branch was greatly increased in weight. In order 



Fig. 5. — A branching 

 corn plant grown in Ohio, 

 perhaps a reversion to an 

 ancestral form. 



