390 Kansas Academy of Science. 



into speculations either unjustifiable or absurd. Inclusive, orderly 

 and corrected results of pure observations in the hands of a master 

 may indeed yield a rich harvest of well-grounded generalizations, 

 as evinced by "The Origin of Species" and the derived theory of 

 natural selection. 



No greater tribute could be paid to Darwin than to recognize 

 that the inexorable logic of his own mental processes quickly car- 

 ried him into the ways of the experimentalists, and no sooner had 

 his interest been fastened upon certain phenomena than he began 

 to arrange cultures, comparative trials and experiments dealing 

 with many important problems in physiology, and bearing upon 

 almost every phase of heredity and descent, and he assiduously set 

 about their execution while the greater number of his followers 

 were still engaged in a conflict of words and a maze of phrase con- 

 struction. 



The interrupted task of bringing evolution within the scope of 

 experimental science so fairly begun by Darwin has been most 

 forcefully completed by DeVries. Like Darwin, his well-consid- 

 ered results obtained by twenty years of experimental cultures 

 have been brought out with a new theory for the interpretation of 

 certain phases of evolutionary development. Without appraise- 

 ment of the importance of ruutation as a factor in evolutionary 

 procedure, it is to be said that the greater service performed by 

 DeVries consisted in his demonstration that the method of trial 

 and test is one by which major phenomena in heredity may be ap- 

 prehended, their course, frequency and scope measured, and by 

 operations of so simple a nature that it has enormously stimu- 

 lated research upon the subjects concerned. 



The general procedure by which we experiment with func- 

 tional features of organisms, or their ontogenetic or morphogenetic 

 development, is too well known to need detailed explication. It 

 consists essentially in setting the organism into action and cali- 

 brating the products, whether these be movements, chemical struc- 

 tures, tissue formations, tropistic reactions, correlations, altered 

 rhythms of reproductive departures. In all of these, develop- 

 mental or evolutionary significance is of course taken into consid- 

 eration. 



Now if attention be wholly directed to genetics, especially in 

 botany, it may be seen that not only have we perfected new methods 

 of investigation but that we have used them to some effect in un- 

 covering principles by which inheritance is governed. Allusion to 

 some of the more important features may not be out of place. 



