abstract the existence of three chemotypes of coridothymus capitatus in israel-a thymol-type, a carvacrol-type and a mixed-chemotype which contained thymol and carvacrol in the ratio about 1:2-was confirmed. a detailed composition of the volatiles of c. capitatus was studied by gc/ms and, excluding thymol/carvacrol ratio, the components of the oils were found to be nearly identical. with the exception of biosynthetically interrelated -terpinene, p-cymene, thymol and carvacrol, the major volatile constituents of c. capitatus were found to be -caryophyllene, caryophyllene oxide, thymohydroquinone and thymoquinone.