Development of the Natural System under [BOOKI. 



displayed. To this purpose he applied morphological re- 

 searches, which in profundity and wealth of thought and 

 in the fruitfulness of their results for the whole domain of 

 systematic botany far surpassed all that Linnaeus and Jussieu 

 had accomplished, and show us that while engaged in his 

 splendid labours in descriptive botany he had caught during 

 his ten years' residence in Paris the true spirit of modern 

 investigation of nature, as it had been developed by the 

 French naturalists of the end of the previous century. Scarcely 

 a trace is to be found in De Candolle of the scholasticism 

 of Cesalpino and Linnaeus, which occasionally makes its 

 appearance even in Jussieu. For instance, he dealt with 

 morphology as essentially the doctrine of the symmetry of 

 form in plants, that is, he found the basis of morphological 

 examination in the relative position and numbers of the 

 organs, disregarding their physico-physiological properties as 

 of no account from the morphological point of view. He was 

 therefore the first who recognised the remarkable discordance 

 between the morphological characters of organs, which are 

 of value for systematic purposes, and their physiological 

 adaptations to the conditions of life, though it must at the 

 same time be acknowledged, that he did not consistently carry 

 out this principle, but committed grave offences against it 

 in laying down his own system. It is a point of the highest 

 interest in De Candolle's morphological speculations, that 

 he was the first who endeavoured to refer certain relations 

 of number and form to definite causes, and thus to distinguish 

 what is primary and important in the symmetry of plants from 

 merely secondary variations, as is seen in his doctrine of the 

 abortion and adherence of organs. In these distinctions 

 De Candolle laid the foundation of morphological views, 

 which, though now modified to some extent, do still contain 

 the chief elements of morphology and the natural system ; 

 but his morphological speculations were confined to the 

 domain of the Phanerogams, and chiefly advanced the theory 



