The genetics of the branching pattern on the cotyledonary laterals of peanuts (Arachis hypogaea L.) was studied through scoring F₁ and F₂ generation progenies from crosses among four lines of Virginia, Valencia, and Spanish types. With one exception, these lines traced directly to gene centers in South America. When results were expressed as the ratio of reproductive branches to total branches (R/R+V), the F₂ from crosses of Virginia × Valencia gave a continuous distribution with the median near that of a Spanish type. Spanish × Virginia crosses gave a continuous distribution in the F₂ with the median equivalent to the Virginia parent. These results suggested that Spanish varieties may have originated from hybridization of Virginia and Valencia types. The presence, or absence, of inflorescences in the mainstem leaf axils of F₂ plants was scored for one cross. The results suggested the presence of two sets of duplicate loci with epistasis among the alleles.