Pharmacognostic Studies onZingiber zerumbet(Linné) Smith and its Proposed Variety (Family Zingiberaceae)

The chemistry of the volatile oils and morphology of Zingiber zerumbet (L.) Sm. and a second plant which is being proposed as a variety reveals significant differences between these two plants. Their main physicochemical differences are the following: dried rhizomes of Zingiber zerumbet (L.) Sm. yield a volatile oil which is dextrorotatory, congeals at 3°C, and has zerumbone as its main constituent. Rhizomes of the proposed variety yield an oil which is levorotatory, congeals at —27°C, and has 4-terpinenol as its main constituent.Significant morphological and anatomical differences between Zingiber zerumbet (L.) Sm. and its proposed variety are noted.On the strength of these physicochemical and morphological differences, which are not sufficient to warrant erection of a new species it is proposed that the other plant be classified as a variety of Zingiber zerumbet (L.) Sm.