A volatile substance known to attract the striped ambrosia beetle, Trypodendron lineatum (Olivier), is produced only by the feeding, mated female. This material may be collected either by extraction from the boring dust with suitable solvents, or by condensation of air passed through the heated frass. Since the attractant was found to be soluble in polar compounds such as ethanol and chloroform, but not in benzene, it is very likely a polar compound. The attractive substance is thermally stable under the conditions necessary to fractionate it on a gas-liquid chromatograph.