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THE AMERICAN NATURALIST [Vol. XLVH1 



sort of variegation, and still others to exceedingly light 

 types of variegation. There can be no doubt that some of 

 these different types of variegation are inherited, but the 

 mode of inheritance in crosses has not been fully worked 

 out. 



One other form of grain coloration that might be called 

 an extremely dark type of variegation is to be noted. The 

 grains are self-red throughout except for a nearly color- 

 less crown formed by converging light stripes extending 

 some way down the side of the grain opposite the germ, 

 almost exactly the reverse of one of the types of dark 

 variegation described above. Variegations of this sort 

 behave in inheritance almost exactly like fully self -red 

 grains, giving a large percentage of red-eared progeny. 

 And these red ears are apparently always fully self-red, 

 never showing the pattern of converging light lines seen 

 in the parent seeds. Many such seeds have been included 

 in the results recorded earlier in this paper where they 

 were listed as " nearly self-red." 



Interpretation of Results 

 Any interpretation of the data presented here must take 

 account of these facts: (1) that the more red there is in 

 the pericarp the more frequently do red ears occur in the 

 progeny, and (2) that such red ears behave just as if they 

 were F 1 hybrids between red and variegated or red and 

 white races. The development of red in the pericarp is 

 evidently associated with and perhaps due to a modifica- 

 tion of some Mendelian factor for pericarp color in the 

 somatic cells. The zygotic formula of a plant homozy- 

 gous for variegated pericarp may be designated as VV, 

 and that of a plant heterozygous for variegated pericarp 

 as V — . If in any somatic cell VV, from unknown causes, 

 a V factor were transformed into a factor for self-color, 

 S, that cell would then have the formula VS. Any peri- 

 carp cells descended from it would without further modi- 

 fication be red. If all the pericarp cells of a seed were 

 thus descended, the seed would be self-red, just as it would 



