110 The Plant World. 



July, 1902), and the appearance of the translation of the first 

 volume of this important work (Open Court Publishing Co., 

 Chicago), affords a fitting opportunity to measure the progress 

 of the ideas presented by its famous author. The arrangement 

 of the present edition was made by Professors Farmer and 

 Darbishire in England, which will do much to lead to a fuller 

 consideration of DeVries' work in that country. There, as well 

 as in America, the earlier presentation of the idea of discontin- 

 uous variation was met with a fine show of prejudice and un- 

 belief, and a tendency was noticeable to prove or disprove its 

 conclusions by citation from Darwin's writings. 



To those most familiar with the broader meanings of the 

 work of the elder Darwin, it would seem that were he alive he 

 would have been among the first to welcome conceptions in which 

 the nature of qualities or characters was more clearly defined 

 and would have encouraged any procedure looking toward the 

 formulation of ideas as to calculable heredity. 



The original publication of the mutation theory was shortly 

 followed by Prof. DeVries' visits to America where experimental 

 tests were first made in substantiation of his results with the 

 evening primroses. By means of lectures, personal meetin3;s and 

 conferences, a large number of Americans quickly gained an 

 idea of the more important features of the mutation theory. 

 A course of lectures at the University of California, whi^h were 

 edited and brought out in a volume under the title of "Species 

 and Varieties" (also published by the Open Court Co.), was still 

 more effective in making known the salient points cf the most 

 important contribution to evolutionary science since the ap- 

 pearance of Darwin's Origin of Species. This book with its non- 

 technical treatment of a difficult subject has been most appro- 

 priately translated into Dutch, German, Italian, and must even- 

 tually be rendered into French and Russian. 



The promulgation of the theory and the description of the 

 experimental methods by which the evidence supporting it was 

 obtained, has stimulated thought and research in evolution enor- 

 mously. The attention of scores of workers in laboratories 

 and cultural establishments has been turned to the testing of 

 various corollaries of the subject, and as has been repeatedly 

 stated, heredity has been definitely brought within the domain 



