of so-called adaptation; if so, processes should be found in 

 nature, analogous to the poisoning of the hyda- 

 thodes in this experiment, which result in the destruc- 

 tion of the hydathod.es so that in consequence the plant 

 would have gained the power of making good the loss, by 

 means of the substitute organs. Such processes, however, 

 (even through poisoning or through parasites) would be 

 very highly improbable. Equally incredible is the alterna- 

 tive possibility that the new organs would be produced by 

 the plant not as a substitute but as a supplementary ap- 

 paratus when the old ones would not sufHce for secretion 

 in case of very large absorption of water. This also must 

 doubtlessly be rejected, as Haberlandt has observed. 



Powers of adaptation should, of course, according to 

 Darwinism, be gradually acquired in the struggle for exist- 

 ence, as in that case they should also have stability; but 

 since this is not possessed by the new organs, the presump- 

 tion is that they do not possess the character of adaptation. 

 They are therefore new organs that originated after an 

 entirely unnatural and unforseen interference with the 

 normal vital functions and in consequence of a self-regulat- 

 ing activity of the organism. 



What then is there in the whole phenomenon worthy 

 of notice with regard to the theory of Descent? 



I. An immediately well adapted new organ has here 

 originated very suddenly without any previous incipient 

 formation, without gradual perfection and without stages 

 of transition. 



58 



