PREFACE TO THE GERMAN EDITION 



IF the botanical historian should ever write an account of that branch 

 of the Botany of our times which is usually termed Morphology, he will 

 probably look upon the period embraced within the last few years of the 

 present century as one of transition. The conspicuous feature of transition- 

 periods is the suppression of directive influences which have been dominant 

 for a time because they are found to have served their purpose and lead 

 no further. Newer views naturally conflict with the old and even with 

 one another ; things are found not to be so simple as was believed, and the 

 old formularies cease to be applicable. 



This change which has been in progress in Morphology is a consequence 

 of the recognition by botanists that the configuration exhibited by plants 

 is a part of their life-phenomena, and is not merely a hypothetical con- 

 struction as it was made by the older idealistic Morphology. All the 

 phenomena of life have a definite relationship to environment, and there- 

 fore, as I shall endeavour to show in this book, the consideration of the 

 configuration of the organs of plants is not merely a comparative historical 

 criticism, but must take into account all the conditions of environment which 

 we find at the present day. Morphology has to determine in what degree 

 the formation of organs shows an adaptation to external relationships, 

 and to what extent it is dependent upon these and upon internal conditions ; 

 and even if the subject be studied from the purely phylogenetic standpoint, 

 such determinations are a necessity, inasmuch as the historical development 

 would be constantly influenced by environment. Phylogenetic speculations 

 are doubtless more attractive than the grappling with the facts, often obscure 

 and apparently insignificant, of the relationships of configuration of the 

 plants around us. It appears to me, however, that to recognize the factors 

 which bring about the development of say a leaf with one side larger than 

 the other is infinitely more important than to construct a phylogenetic 

 hypothesis unsupported by facts. 



