new characters and did not revert to the ancestral Lamarck- 

 iana; these were the mutants, the new elementary species, 

 which had sprung suddenly in a saltatory fashion from the 

 parent stock. The great importance lies in the fact that 

 they were entirely constant to their new characters, and 

 were thus not in the class of the merely unstabjg varieties. 

 It must be remarked that time alone, many generations, 

 of carefully guarded cultures in which accidental cross- 

 ing was an impossibility, together with unimpeach- 

 able records, could adequately establish this momentous 

 fact, that here was a new species, a new form, or what- 

 ever you may elect to call it, which had sprung all in one 

 jump from its parental stock. De Vries, then, was the first 

 man who ever saw a new type of organism come into the 

 world and who recorded its advent. 



You naturally ask how unlike were these new forms, a 

 question which is difficult to answer without actual illus- 

 trations. However, it may be said that many of them 

 were different enough from their parent stock to be ad- 

 mitted by taxonomists to come within the definition of 

 new species, as species are regarded at the present time. 

 The differences are not the question of mere stature, but 

 of the whole habit of the plant and of the details of 

 the form of both leaves and flowers. But to repeat, 

 it really makes no odds whether the differences are 

 of such quality that they must needs be recognized as 

 specific by taxonomists ; what is important is that they are 

 differences which do not intergrade one with another and 

 which are inheritable in the second, third and subsequent 

 generations, and that no tendency to revert to the parent 

 form is to be observed. 



The results of De Vries have been verified by cultures in 

 this country of his own and of other stock, so that there 

 can be no question that this Lamarck's evening primrose 

 behaves in its manner of mutation the same here as else- 



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