Purpose of Nomenclature

  For most societies plants are major sources of food, medicine and other essential products and so over time each species has acquired a name which may differ from place to place making it difficult for potential users to share their knowledge. Hence it is not surprising that one of the earliest botanical records is a list of medicinal plants from the Euphrates Valley along with their equivalent names in the Nile Valley. The need for such lists arises whenever the same species is known by different names in the same or different places. Likewise, it is important to be aware that when the same name is applied to different species failure to distinguish between the two may have disastrous consequences. For example, in Australia, Solanum nigrum is widely known as Deadly Nightshade, notwithstanding that its ripe berries are not poisonous (Everist 1979) and often eaten. In contrast eating the similar looking berries of the English species known as Deadly Nightshade (Atropa belladonna) could be fatal. To avoid the confusion that can result from a species having more than one name, or different species having the same name, an international system of nomenclature has been devised. Because the originators of the system were Europeans, for whom the language of scholarship was Latin, the Swedish author of the pioneer text on the subject (Linnaeus 1753) wrote in that language. The Latin he employed, specially for describing plants, differed considerably from that of Classical Times and like Ecclesiastical Latin is always evolving with an expanding vocabulary to account for new structures and ideas. This subject is admirably dealt with by Stearn (1992) who in his “Botanical Latin” discussed many of the problems associated with the formation of binomial names and provided a synopsis of the views propounded by Linnaeus (1753) on the subject.

  In “Species Plantarum” Linnaeus assigned every species to a genus and each was briefly described. In the margin beside each description was a single italicized word which usually referred to some salient feature of the species. This word together with the generic name became known as a binomial. Today the binomial is the basis of the nomenclature by which all species are known internationally. The application of these names is controlled by an “International Code of Botanical Nomenclature” (Greuter 2000) which is subject to periodic revision. The objective of the Code, which encompasses all taxonomic ranks up to and including Family, is to stabilize nomenclature so that each plant has only one name, thereby making it easier to search the literature for information concerning taxa and especially species. Since the generic and specific names derive from many sources their meanings are often difficult to determine, unless the reader has access to a large botanical library.