Genes of anthocyaninless were transferred by backcrossing to G.barbadense L. and genes of Pima S 6 were transferred by backcrossing to G.hirsutum L. A fourth backcross F₂ to Pima S 6 nectariless indicated that anthocyanin was produced by a single gene at the R² locus and resulted in a large petal spot, pinking petals and anthocyanin in petioles, stems and leaves. As in the PS 6 parent, the gene at r(1) in PS 6 ne was a null gene. The frequency of anthocyaninless was one-fourth. In G.hirsutum when sun-red or red R(1) types are parents, anthocyaninless is 1/16. The R²(np) action is not completed with r(1)(np) and anthocyaninless results. The r(1)(np) and r(1)(p) are allelic if not identical. The R²(np) interaction within PS 6 is an ephemeral white area in the petal-spot position of the yellow petal. The R²(np) of anthocyaninless behaves similarly to the ghost petal spot of the A Gossypium diploids, and its size suggest a likely origin from the related B diploid G.anomalum. At the diploid level ghost petal spot is not detected on ivory white petals but shows as a white petal spot on the yellow petals. The active R²(p) of Pima in G.hirsutum loses size, intensity, and is variable in appearance in petals. When the linkage R²(p) Yg(2) Cl(2) is followed and homozygous 2 R²(p)Yg(2) Cl(2) is present the sun red plants generally fail to produce a petal spot of large size, presence on each petal, etc. The penetrance of R²(p) and its expressivity is altered in G.hirsutum. However when the linkage yg(2) cl(2) having the short-branch cl(2) of "old" Pima was followed in G.hirsutum, the accompanying pencil mark sized, varying in frequency, petal spot increased in size, intensity and frequency. The expression of cl(2) also changed, becoming long sympodia that terminated in multiple flowers rather than the one or two node short-branch.