144 SOUTHERN FIELD CROPS 



words, of the seed slio-\ying dominant qualities some are purs 

 dominants and some are mixed, though ha^'ing the same appear- 

 ance as the pure dominants. 



131. Practical results. — Practical application may be 

 made of the somewhat technical statements in the last few 

 paragraphs in tlie folloy\'ing way, and in other operations 

 in plant breeding ; — 



(1) After crossing pollen of a pure yellow variety on 

 silks of a pure white variety, say in 1910, practically all 

 of the grains of the current cross in 1910 may be expected 

 to be yellow or yellowsh ; all the pure white gi-ains found 

 in the second generation among the descentlants of. this 

 cross may lie considered as pure-bred so far as concerns 

 color, and these white grains may be expected in all future 

 years to produce onl}' white grains. 



(2) After crossing pollen of a pure white variety on 

 silks of a pure red variety, all the grains of that current 

 cross will be red (because the hull of the grain is furnished 

 by the mother parent, uninfluenced bj- the pollen used in 

 the current cross) ; -wlien these red grains are subsequently 

 planted, the crop will contain a majoritj' of red grains, 

 most of which will ))e impure, as shown by their descend- 

 ants, bearing both red and white grains. 



On the other hand, the white grains, found in the second 

 generation in smaller number among the retl grains, are 

 pure; and when these white kernels are planned, their 

 offspring will consist entirely of white kernels. 



132. Relative value of top and bottom ears for planting. 

 — When th(>re is any consideralile inequality in size be- 

 tween two ears growing on one j^lant, the upper ear is 

 generally the larger. 



