Although cis-11-tetradecenyl acetate is a sex attractant for males of several species of moths these species responded selectively to subtle quantitative or qualitative changes in the composition of the odor stimulus. It is plausible, based on the odor-discrimination capability of the moths, that moths of many species could use pheromones of identical chemical structure and avoid interspecific pheromonal confusion by responding only to specific concentrations and/or blends of chemicals characteristic of their own species.