paenell, rancaswami ayyangar, and eamiah 99 



Table XVIII, 



The right side of the table shows that, in each family, the simple ratio of 

 blade : straiv is 3 : 1, clue to segregation for a single factor. The figures on tlie 

 left clearly indicate partial repulsion between this factor and the purple lining 

 factor. Unfortunately in No. 849-N the full figures are not available since 

 only the straio plants were examined with regard to internode. It is obvious, 

 however, that in all three families the repulsion was approximately of the 

 same degree. 



The degree of repulsion is of interest since, as seen by the calculated 

 figures, it is definitely intermediate between the two recognized reduplication 

 ratios — 3:1 and '/' ." 7.* 



When both lipening black factors are segregating it appears that both 

 are subject to partial repulsion by the lining factor. The few famifies for 

 which figures are available show considerable irregularity in their ratios, 

 suggesting varying degrees of repulsion, but further results are necessar}'- before 

 a definite statement to this effect can be made. 



It is of interest to notice that where both ripening black factors are subject 

 to this partial repulsioi\ they come together oftener than would otherwise 

 be the case and the ordhiary D : 7 ratio is upset. This explains certain 

 irregular results that had been very puzzling before the cause was known. 

 Thus from a family giving a black : straw ratio of D : 3-S further generations 

 gave a mixture of definite 3 : 1 ratios together with others varying from 



* Three families of a later crop have given about the same degree of repulsion. 



