1. MORPHOLOGICAL ADAPTATION 



Morphological adaptation is a well-established fact, and 

 I need only mention the striking differences between the 

 land and water form of amphibious plants, or the differences 

 between the same species of plants in the Alps and in the 

 plains, or the very different aspect of the arms of an athlete 

 and of an ascetic, to recall to your memory what is meant 

 by this term. 



Morphological adaptation is no part of individual 

 morphogenesis proper, but occurs at the end of it ; at least 

 it never occurs previous to the full individual life of an 

 organism, previous to its true functional life ; for it relates 

 to the functions of the complete organism. 



THE LIMITS OF THE CONCEPT OF ADAPTATION 



It is especially, though by no means exclusively, among 

 plants that morphological adaptation assumes its most 

 marked forms ; and this topic, indeed, may very easily be 

 understood if we remember that plant-life is in the very 

 closest permanent dependence on the medium, and that 

 this medium is liable to many changes and variations of 

 all kinds. In order to elucidate our problem, it therefore 



seems convenient to restrict our considerations for a while 



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