MUTATION IN (ENOTHERA 145 



formation of the pollen was very defective. None of 

 the others was lacking in either of these respects. Each 

 new form was distinguished by certain definite features 

 which affected almost all its parts, not by one new 

 character only ; and these features were never separable, 

 but always appeared in common on the same plant. 



The new species, of course, showed normal fluctuat- 

 ing variability, and, as an extreme result of this varia- 

 bility, forms occasionally appeared midway between 

 one of the new species and the parental type. In such 

 cases, when the self-fertilized seed of the plant showing 

 such an intermediate character was sown, the offspring 

 were found to group themselves round the normal 

 form of the new species or round that of the parent 

 Lamarckiana, thus affording evidence as to the true 

 nature of their parent. 



Whether or not we are prepared to accept the whole 

 of de Vries' conclusions from his experiments, we can 

 see at least that from one point of view they are of the 

 very greatest importance. For before de Vries pub- 

 lished this work it had been supposed to be quite im- 

 possible to make direct observations upon the manner 

 of origin of new species in Nature. De Vries has now 

 shown that such observations can be made, and this is 

 in itself a most valuable piece of information. He has 

 introduced an entirely new method into the domain of 

 species research, and one by the use of which it is to be 

 hoped that before long a definite answer will be obtained 

 to the question whether species in general arise by defi- 

 nite steps, or with an imperceptible degree of slowness. 



When results of the novelty and importance of those 



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