356 



Journal of Agricultural Research voi. xxu.no. 7 



probable error it may be regarded as being very significant. As there 

 is a significant correlation between these two generations, the variations 

 under consideration are not fluctuations due to external conditions but 

 are hereditary variations. 



Table XI. — Correlation table showing the classes of spelt inheritance o/Fj heterozygous 

 plants, with the average degree of spelling of the F^ progeny of each F-^ plant (series Ij2j^a 

 and 12260a) 



Classes of spelt inheritance (Fs) 



CoeflBcient of heredity=o.88o±o.o29 



If there were no interference due to modifiers, the curve of the spelt 

 F3 progeny of the heterozygous Fj individuals would follow the spelt 

 curve of the Fj generation, as both the spelts of the Fj curve and those 

 of the F3 curves of heterozygous Fg individuals consist of SS and Ss 

 spelt plants in the proportion of i to 2, respectively. 



An examination of the F3 spelts of heterozygous individuals in Table X 

 shows that the curves of the 13 families vary considerably from the curve 

 of the F2 generation (Table I, series 13260a), although the curve for the 

 totals is much the same. 



Again, if there were no genetic interference, all the F3 progeny curves 

 produced by heterozygous F2 plants would be expected to follow more or 

 less the same course. The experimental results exhibit wide differences, 

 as the comparison of the classes of individuals i326oa-3, -6, -7, etc., 

 will readily show. 



