“Mutation in the evening primrose,Onagra biennis (L.) Scop.,” with demonstrations

Culture experiments by the authors confirmed MacDougal's discovery of a narrow-leaved mutant of this species. From purely pollenated seed obtained by MacDougal and Britton from a wild plant growing at the New York Botanical Garden, 499 seedlings were obtained, of which 3 belonged to the narrow-leaved type. It is possible that a second mutant was found, but further observations are needed to confirm this. The species used by the authors is not O. biennis studied by de Vries.