abstract the essential oils of hyssopus officinalis l. var. decumbens (hod) from france (banon) and h. officinalis (ho) from italy (piedmont) were studied by gc and gc/ms. the bicyclic monoterpene ketones, pinocamphone and isopinocamphone, were present in ho (4.4% and 43.3%, respectively, in accordance with the iso 9841 standard, 1991 e), but their percentages were very low in hod, where instead linalool (49.6%), 1,8-cineole (13.3%) and limonene (5.4%) were predominant. key word index: hyssopus officinalis hyssopus officinalis var. decumbens lamiaceaeessential oil compositionpinocamphoneisopinocamphonelinalool1,8-cineolelimonene