SUBGENERIC AND SECTIONAL NAMES: THEIR STARTING POINTS AND EARLY SOURCES

Summary Because of the great difficulties associated with the determination of the correct names of infrageneric taxa of vascular plants, the development of the concepts of subgenus and section (sectio) and the use of these terms are traced from the time of Linnaeus to the mid‐nineteenth century. It is argued that the year 1805, which marked the mass introduction of subgenera (by Persoon) and of sections (by A. P. de Candolle) should be adopted as the starting point for the valid publication of names of taxa of vascular plants between the ranks of genus and species. (See Taxon 17: 659. December, 1968, for the formal proposal for the adoption of 1 January 1805 as starting point). A number of nomenclaturally important taxonomic works and floras of the nineteenth century which have become sources of confusion in regard to subgeneric and sectional names are also considered more or less in chronological sequence. Included are works by Persoon, S. F. Gray, Mertens, W. D. J. Koch, Dumortier, Link, Reichenbach, Torrey, A. Gray, Endlicher, K. Koch, Dippel, and von Post & Kuntze. It is concluded that subgeneric and sectional names must be interpreted in terms of the word actually used to denote the rank of the taxon to which the name is applied and not in terms of the author's concept of infrageneric categories: what the author actually did is of greater importance than his guessed intentions . Hence, although Endlicher, for example, possibly intended to recognize several infrageneric ranks, his failure to indicate the rank of his generic subdivisions has to be decisive.