MKNDKLISM LN OATS 



In Ihc upiKT row arc .Svalof's Klock Oals II (at the k-ft) and Svalof's SlormoRul Oats (at the 

 right) Each of these "pure Hne" sorts has one mendelian factor which causes spreading 

 panicles. The factf)r in Klock Oats (Al) is, however, distinct from that in .Stormogul (A2). 

 When the two sorts arc crossed, the genetic formula will be Ala2 x alA2, capital letters 

 denoting presence of the factor for spreading panicles, and small letters absence of it. \V hen the 

 factors are distributed and combined in the germ-cell, f)ne comlnnation will arise lacking both 

 positive factors, and represented bv ala2. As this oat will lack allogi^lher a factor to spread 

 the panicle, its appearance will necessarilv be quite different from tliat of eitlier parent; as a 

 matter of fact it grew up to be a "sidewav panicle" oat, shown at tlie right in the lower row. 

 Another combination of the factors brought lioth ])ositive factors (AIA2) together in the same 

 cell; and the oat with this "double df)se" of spreading-panicle factor appears to be even more 

 spreading than either parent. It is shf)wn in the lower row, at the left. The rest of the oats 

 from this cross were represented by the factors A 1 al or a2 A2— that is each possessed one factor 

 for spreading. These two types, when grown, were indistinguishable, and looked alKnit like 

 their parents, as shown in the center of the lower row. (Fig. 6.) 



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