Neither allele in snapdragon flower color is dominant. The F1 generation exhibits an intermediate phenotype.
The genotypic ratio (1:2:1) of the F2 generation is identical to that of Mendel's monohybrid cross, but the phenotypic ratio is identical to the genotypic ratio.
These phenotypes are due to the production of a red pigment by the R enzyme; the R2 allele produces no pigment; a heterozygote produces half as much pigments as the homozygous R1 and appears pink.