[Vol. LII 



The above data are believed to show conclusively that the C 

 factor for aleurone is linked with the factor for waxy endosperm, 

 because the B and A testers caused the development of aleurone 

 color when crossed with colorless individuals from the same fam- 

 ily while the C tester did not. 



Non-Linkage op Aleurone Color and Waxy Endosperm 

 It is interesting to know that in ear 10, which shows no linkage, 

 the C factor for aleurone was not heterozygous. A colorless 

 waxy individual from this family crossed with the C tester pro- 

 duced an ear consisting of approximately 300 seeds, all of which 

 showed colored aleurone. 



Another waxy colorless individual of the same family crossed 

 with the B tester produced an ear with 25 seeds, all of which 

 were colored. Thus the C and B factors are eliminated with 

 some degree of assurance. The A factor apparently is heterozy- 

 gous in this family, but unfortunately the writer has obtained 

 no crosses with the A tester to verify the conclusion reached by 

 the process of elimination. This may be considered as indirect 

 proof of the C factor as the aleurone factor which is linked with 

 the waxy endosperm factor. 



(a) Collins has presented conclusive evidence of the linkage 

 between waxy endosperm and aleurone color. The writer has 

 presented additional evidence from back crosses, which shows the 



