Page:Makers of British botany.djvu/60

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ROBERT MORISON AND JOHN RAY

temporary arrest almost everywhere, except in France, of the quest of the natural system. Though this was the effect of the introduction of his method, it was not at all the intention of Linnaeus: for in his Classes Plantarum (1738, p. 485) he said, "Primum et ultimum in parte Systematica Botanices quaesitum est Methodus Naturalis." On the same page of that work he laid down, in a series of aphorisms, the principles upon which alone the construction of such a method can be successfully attempted; and he gave special emphasis to this one, that the classificatory characters should not be taken from a single structure but from all: "nec una vel altera pars fructificationis, sed solum simplex symmetria omnium partium." It was just because they had failed to formulate this principle that the earlier systematists,—whether Fructists, as Cesalpino, Morison, Ray, Knaut and Hermann; or Corollists, as Rivinus and Tournefort; or Calycists, as Magnol—were not more successful, and that their systems, even the Methodus emendata of Ray, were more or less artificial.

It was in France that the carving out, as it were, of the Natural Orders from the solid block of genera was carried on with the greatest success. This process had become much less difficult since Tournefort had begun to constitute genera in the modern sense of the term. Before his time the word "genus" had been applied indiscriminately to every kind of plant-group (see the systems of Cesalpino and Ray, pp. 12, 32): the largest groups were the summa genera; the smaller, the genera subalterna or infima. Tournefort limited the application of the term to the smallest groups of species, designating by the term Classe the largest groups which he subdivided into Sections (Elemens de Botanique, 1694). It was Linnaeus (Classes Plantarum, p. 485) who introduced the term Ordo to designate the subordinate groups of the classes.

Tournefort himself succeeded, by means of his corollist method, in distinguishing for the first time the following Sections, describing their flowers by terms which are now familiar as the names of natural orders; Flore Labiato, Cruciformi, Rosaceo, Caryophyllaceo, Liliaceo, Papilionaceo, Amentaceo; though these sections do not all exactly agree with the modern