No. 597] INHERITANCE STUDIES IN PlsUM 541 



Nott's Excelsior X Groldkonig 

 Aldermann X Groldkonig 

 Scotch Beauty X Groldkonig 

 Sutton's Main Crop X Groldkonig 



An F 2 generation has been grown from the first three 

 of these crosses with the results (see Table IIIc) ap- 

 proximating a ratio of 3 G : 1 Y or the reverse of the com- 

 mon result. Practically all of the green seeds are distinct 

 greens, but among those classed as }^ellows are several 

 doubtful cases, and these are marked questionable. An 

 F 3 generation is being grown which will decide whether 

 I have erred in considering these doubtful cases as yellow 

 cotyledon peas in which the greenish color results pos- 

 sibly from lack of enough sunlight during the ripening 

 period. 



When the "Groldkonig" yellow was crossed with other 

 varieties having yellow cotyledons, the F 1 progeny all had 

 yellow cotyledons, but in the F 2 generation, a certain pro- 

 portion of peas with distinctly green cotyledons appeared, 

 the F 2 ratio in the progeny of the ten different Fj plants, 

 showing considerable variation, but averaging 13 yellow 

 seeds to 3 green seeds, provided all yellows having any 

 considerable amount of green pigment are classified as 

 greens. The number of F 2 generation progeny obtained 

 was small, totaling only 566, of which 457 had yellow 

 cotyledons, 87 distinctly green cotyledons and 22 seeds 

 had yellowish green cotyledons. All were grown under 

 conditions insuring their maturity, but under these con- 

 ditions (greenhouse cultures) the amount of moisture 

 present is such as possibly to cause some of the true 

 greens to bleach. Further justification for classifying 

 the 22 doubtful greens as true greens comes from the fact 

 that all the varieties having yellow cotyledons used in 

 these crosses with the exception of Goldkonig are varie- 

 ties with distinctly bright yellow cotyledons, which grown 

 under the same conditions and often side by side with the 

 crosses, never show any green coloring matter in the coty- 



