Aug. 6, 1917 



Studies on Oat Breeding 



303 



Table III. — Relation between the hull character and the grain color 



From this table it is evident that the observed numbers agree fairly 

 well with the expected and show that the genes for the hull character 

 and grain color segregate independently. As mentioned earlier, the 

 intermediate forms show a greater resemblance to the hull-less oats 

 than to the hulled forms. If the plants with intermediate and hull-less 

 grain are grouped together, a still better agreement between the observed 

 and expected numbers is obtained. This is shown in the Table IV, 

 where the expected numbers are calculated on the 9:3:3:1 ratio. 



Table IV. — Relation between the hull character and the grain color 



C. — PUBESCENCE AT THE BASE OP THE GRAIN 



Another character involved in this cross is the pubescence at the base 

 of the grain. The conditions in regard to this character are somewhat 

 complicated by the nature of the naked parent. The character of the 

 pubescence can only be established for the hulled Victor parent and for 

 the hulled progeny, while it is obvious that in the case of the naked 

 parent and all the naked forms of the segregating progeny the manifesta- 

 tion of that character is impossible. Moreover, there is evidence that 

 also in the majority of the intermediate forms of the second generation 

 the total or partial nakedness of the lower kernels interferes with the 

 normal manifestation of the pubescence. This causes a deviation from 

 the expected type of pubescence, which will be discussed below. In 

 grouping the intermediate forms of Fg in regard to pubescence it is often 

 difficult to decide whether a given plant does not carry the factor for 

 pubescence at the base of the grain or whether its manifestation is only 

 foiled by the fact that the grain is not inclosed in the firm glumes. 



In studying the inheritance of this character it may be well to con- 

 sider first the plants in which the hull character does not interfere with 



