8 HISTORY OF BOTANY 



contained several hundred cultivated herbs, shrubs, and 

 trees, at least he mentions some five hundred species in 

 his two books. He recognised that the aerial supports 

 of an ivy were roots and not tendrils, and that all under- 

 ground parts are not necessarily roots ; in other words, 

 he appreciated, to some extent at least, the difference 

 between true roots and rhizomes. The sepals and petals 

 of the flower are modified leaves, so that the flower is to 

 be regarded as a metamorphosed leafy branch. The root 

 is defined as that part by which nutrient materials are 

 taken up from the soil, a physiological definition, as is 

 also his definition of the stem, viz. the chief means of 

 transport of the nutrients to other parts. Theophrastus 

 does not attempt to define a leaf, but he describes very 

 fully the different kinds of leaves known to him. 



Although he had no lenses, save those with which 

 Nature had provided him, he shows himself possessed 

 of a general knowledge of the rough anatomy of the 

 different plant organs. He indicates the essential 

 differences in stem, leaf, and seed between Monocotyledons 

 and Dicotyledons, and has a fairly clear conception of the 

 mode of formation of annual rings. Indeed he devotes 

 two chapters of his Enquiry to anatomy, and nothing 

 of any importance was added to his statements until the 

 days of Grew and Malpighi in the seventeenth century a.d. 



Ignorant as he was of the precise functions of sepals, 

 petals, stamens, and carpels, he laid the foundations of 

 our knowledge of floral morphology, for he distinguished 

 between what he called " leafy flowered " and " capillary 

 flowered " plants, i.e. between what we term petaloid and 

 apetalous flowers, between hypogynous, perigynous, and 

 epigynous insertion of floral leaves and " capillaries " or 

 stamens, and between centripetal inflorescences like that 

 of a foxglove and centrifugal ones like that of chickweed. 

 He knew that a capitulum consisted of many flowers, a 

 fact not always clearly realised even in the twentieth 

 century by the junior student in our universities. The 



