234 MENDELISM 



inheritance of a number of comparatively simple 

 characters, many of which have little practical impor- 

 tance. But the fact of their strictly Mendelian be- 

 haviour showed the possibility of readily obtaining any 

 desired combination of them, and at the same time 

 rendered it highly probable that characters of a more 

 practical value to the farmer would prove similarly 

 amenable to the breeder's art. 



Thus Biff en found that the following pairs of 

 characters, among others, exhibited simple Mendelian 

 phenomena, the one placed first being in each case the 

 dominant : 



Beardless ears. Bearded ears; 



Keeled glumes. Round glumes. 



Felted glumes. Glabrous glumes* 



Red chaff. White chaff. 



Red grain. White grain. 



Thick and hollow stem- Thin and solid stem. 



And so on. In other cases, again, the F x generation 

 showed a character intermediate between those of 

 the parents, and in F 2 there appeared a ratio corre- 

 sponding to A : zAa: a. 



Thus when Polish wheat (early) was crossed with 

 Rivet wheat (late), the time of ripening of the F x 

 generation was intermediate between those of the 

 parents. In F 2 , 103 early, 210 intermediate, and 

 100 late plants, were counted. Time of ripening is, 

 moreover, clearly a character which may be of con- 

 siderable practical importance. 



In further illustration of what can be done from a com- 

 mercial point of view, we will consider the case of two 

 other characters only rust immunity and ' strength/ 



