INHERITANCE— IMPROVEMENT BY BREEDING 199 



increased variability in F 2 (see Table XXXIX) is the direct CHAP, 

 result of segregation. • 



156. Inheritance of Size and Weight of Grain. — East and 

 Hayes conclude that segregation occurs in the progeny of 

 ears heterozygous for size and weight of grain. 



Fig. S3. — Inheritance of row numbers. A, io-row Hickory (Louisiana). 

 B, Hickory with 10 rows below and 8 above. 



157. Inheritance of Row Numbers.- 



of grain in an ear varies according to the breed 



The number of rows 

 In some 



breeds it is more definitely fixed than in others, e.g. Hickory 

 King ; many of the flint breeds are normally 8-rowed and 

 rarely exceed that number when pure-bred ; in these cases an 

 ear carrying more than 8 rows is considered untrue to type, 



