FERTILITY 



203 



(that have been to a large extent made pure) are crossed, 

 the offspring is more vigorous than either parent (Fig. 



FIG. 98. At left an ear of Learning Dent corn, and another at right 

 after four years of inbreeding. The hybrid between the two is shown in the 

 middle ear. (After East.) 



97). This is clearly shown in the accompanying pic- 

 tures. Not only is the hybrid plant taller and stronger, 

 but in consequence of this, no doubt, the yield of corn 



