abstract the leaf oils of the four species which comprise the melaleuca minutifolia group have been examined by gc and gc/ms. the leaf oils of m. minutifolia contained a mixture of both mono- and sesquiterpenes, with -pinene (16-20%) bring the principal monoterpene. the main sesquiterpenes present in the oil were aromadendrene (3-11%), bicyclogermacrene (5-10%) and -, - and -eudesmol (7-11%, 5-7% and 8-12% respectively). melaleuca monantha produced an oil which was much richer in -pinene, 20-54% from one site and 66% from a second site accompanied by lesser, though still significant amounts of -pinene (14-30% from one site and 2-9% from the second site). melaleuca sylvana produced an oil in which -pinene (26-62%) was the principal component. the main sesquiterpenes were -caryophyllene (5-13%), bicyclogermacrene (3-11%). the leaf oil m. uxorum contained -pinene (5-17%), bicyclogermacrene (6-13%), globulol (8-14%), spathulenol (6-14%) and viridiflorol (3-10%) as the main components. pca analysis supports the taxonomic distinctness of the four species.