HEREDITY 



The matter should be easy of determination 

 by observation of considerable numbers of i\ 

 and F 2 offspring. Investigations are now in 

 progress to test this matter. 



My colleague, Dr. East, has found clear evi- 

 dence that, in maize, size-characters, although 

 they give a blending result in Fj, nevertheless 

 give segregation in F 2 . The character to be con- 

 sidered relates to length of ear in corn. A single 

 illustration will suffice. The variation in two 

 pure varieties is shown in the two upper rows of 

 Fig. 48. The " Length " of each class is given 

 in centimetres, its frequency just below at ' ' No. 

 Var., ' ' abbreviation for number of variates. The 

 variation in the F x offspring obtained by cross- 

 ing the two pure varieties is shown in the third 

 row, and that of the F 2 offspring in the lowest 

 row. Note that the variability in the F x gen- 

 eration is not increased; its range is interme- 

 diate between the range in the parental varie- 

 ties. In the F 2 generation, however, the varia- 

 bility is so increased that it includes almost 

 the entire range of both parental varieties, to- 

 gether with the intervening region. 



In the light of this evidence it is clear that 

 138 



