Plantarum. The latter is essentially physiological, touching upon agriculture to a certain extent: the former is mainly morphological, structural, descriptive, and it is here that the first attempt at a classification of plants is to be found. In writing the Historia, Theophrastus was endeavouring, as a Greek philosopher rather than as a botanist, to "give account of" plants; and in order to do so he found it necessary to arrange them in some kind of order. Seizing upon obvious external features, he distinguished (Lib. I. cap. 5) and defined Tree, Shrub, Undershrub and Herb, giving examples; adding, however, that the definitions are to be accepted and understood as typical and general, "for some may seem perhaps to deviate" from them. Simple as was this mode of arrangement, Theophrastus further simplified it in the course of his work, by treating trees and shrubs as one group, and undershrubs and herbs as the other.
It may seem, at first sight, singular that a lecture purporting to discuss the state of systematic botany in England during the 17th century should begin with a reference to the botany of the Greeks. The explanation is that the elementary classification introduced by Theophrastus persisted throughout the 17th century; the use of the groups Trees, Shrubs, and Herbs came to an end only in the 18th century, with the advent of Linnaeus. It seems almost incredible, but it is a fact, that the lapse of the nearly 2000 years that separated Theophrastus from Morison marked no material advance in the science of classification. Botanical works, when they were something more than commentaries on Theophrastus or Dioscorides, took cognizance of little else than the properties, medicinal or otherwise, of plants, and their economic uses.
A growing perception of the essential resemblances observable among plants can be traced, however, in the later Herbals, as they became less medical and economic and more definitely botanical. Thus, in the well-known work of Leonhard Fuchs (Fuchsius), De Historia Stirpium Commentarii, 1542, the plants are described in alphabetical order, without any reference to their mutual relation. But in Kyber's edition of Jerome Bock's (Tragus) De Stirpium Nomenclatura, etc., Commentariorum Libri Tres, published in 1552 (with a preface by Conrad Gesner), there
