The volatile components of metasternal gland extracts of male and female Megacyllene robiniae have been analyzed by gas chromatography-mass spectroscopy. 2. The major component was identified as 2-(1,3-hexadien-1-yl)-5-methyltetrahydrofuran, a new natural product. 3. 1-Phenylethanol is present only in male extracts. 4. Acetates of hexadecanol and octadecanol are also present.