THE EFFECTS OF HYBRIDIZING 



51 



the pollen grain unites with the egg cell, and very soon growth 

 begins. 



Hybridizing. When the pollen comes from another variety or 

 type of corn, the ear produced is then said to be " crossed," or is a 

 hybrid ear. All kinds of corn will cross naturally if planted near 

 enough for pollen 'to be carried by the wind (Fig. 21). 



FIG. 20. Method of preparing a laboratory exercise, and also showing in detail the male 

 (from tassel) and female (from ear) flowers of corn. 



Crossing is often done artificially. The ears and tassels of plants 

 to be crossed are first covered with paper bags (Fig. 21), before the 

 silks have appeared or pollen is shed. In a few days, when the silks 

 have appeared, pollen is taken from another plant and applied to the 

 silks. 



The Effects of Hybridizing. When two varieties of corn are 

 hybridized or crossed there is some direct effect seen the first year, 



