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Many insects depend on odors to lead them to sources that supply their basic needs. Knowledge of these behavioral patterns helps to combat insects of economic importance. For example, attractants in traps offer a remarkably simple means of detecting insects and may even be useful in direct control. They are increasing the efficiency of insecticide applications because treatments need be applied only where insects are caught and only as long as they are caught.

The sex attractant produced in extremely small amount by the virgin female pink bollworm moth has been isolated in pure form and identified as 10-propyl-trans- 5, 9-tridecadienyl acetate. Successful synthesis of this molecule confirms the structure and makes possible its practical use to help control this destructive pest of cotton. The attractant, for which the common name "propylure" is suggested, may be the first naturally occurring compound with propyl branching to be reported.

The recently isolated sex attractant of the female American cockroach elicits an electical response in the antennae of males, females, and mymphs of this species. These electroantennograms are known to be summated receptor (generator) potentials of many olfactory sensillae stimulated simultaneously. Many other odorous substances also elicit such responses in the cockroach antenna.

The highly potent sex attractant of the female American cockroach, Periplaneta americana (L.), has been isolated in pure form and identified as 2,2-dimethyl-3-isopropylidene-cyclopropyl propionate. The hydrogenated form of the attractant has been synthesized.

The extremely potent sex attractant of the female gypsy moth has been isolated in pure form and identified as dextrorotatory 10-acetoxy-1-hydroxy-cis-7-hexadecene. The dl-form of the attractant has been synthesized.

The structure (2,2-dimethyl-3-isopropylidenecyclopropyl propionate) previously assigned to the sex attractant of the American cockroach has now been shown by additional physical and chemical data and biological inactivity of the synthetic preparation to be incorrect. The structure of this attractant remains to be determined.