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THE AMERICAN NATURALIST [Vol. XLVIII 



If the interpretation suggested here is correct, it is to 

 he expected that the more red there is in the pericarp of 

 any seeds, i. e. f the larger the mass of tissue descended 

 from the cell in which the change from V to 8 took place, 

 the greater the chance that the female gametes concerned 

 carried the factor 8. With heterozygous, variegated- 

 eared plants, F — , however, never more than half of the 

 gametes concerned could carry S even in case of self-red 

 grains, the other half of the gametes carrying no factor, 

 — . Of the heterozygous, variegated ears the progenies 

 of which have been reported here, some were self ed, some 

 crossed with white, and some open-pollinated. From self- 

 pollinated ears, self-red and nearly self-red seeds yielded 

 32 red-eared, 9 variegated-eared, and 14 non-red-eared 

 plants, or practically 58 per cent, self-red. This excess of 

 self-red ears may be due, in part at least, to the presence 

 of the 8 factor in some of the male gametes concerned, but 

 the numbers are too small to give very reliable indica- 

 tions. From similar ears that instead of being selfed 

 were crossed with white, so that the results could not have 

 been influenced by factors present in the male gametes, 

 self-red and nearly self-red seeds produced 14 plants with 

 red ears and 13 with non-red ears, or about 52 per cent, 

 red. While these numbers are very small, the fact that 

 no variegated ears were produced, but that every ear with 

 any red color was self-red, is noteworthy. From the 

 open-pollinated, heterozygous ears included in my cul- 

 tures self-red seeds gave progenies consisting of 171 red- 

 eared, 32 variegated-eared, and 102 non-red-eared plants, 

 or about 56 per cent. red. 



In case of homozygous, variegated-eared plants, VV, all 

 the gametes associated with seeds that later become self- 

 red could carry S only if both V factors of the somatic cells 

 from which the gametes arise were changed to S factors. 

 Because of the rarity of changes from V to S, unless both 

 V factors are influenced alike by whatever causes the 

 change, so that both change simultaneously to 8 factors, 

 the chance is slight that more than one will ever change. 



