MIRACLES OF SCIENCE 



ties, has produced equally striking and rather more 

 definite results. By subjecting the eggs of the 

 beetles to different degrees of temperature and 

 moisture from those in which they usually live, he 

 was able to produce certain color mutations at desire. 

 These and similar experiments made it seem 

 probable that new races of plants and animals have 

 appeared through mutations in the past and are likely 

 to appear at any time when through voluntary or 

 involuntary migration a species of animal or plant 

 is brought under the influence of a changed environ- 

 ment. But the development of the new race, though 

 we may suppose it to be much more rapid than had 

 hitherto been imagined, need not depend upon any 

 principles divergent from those which Darwin orig- 

 inally expounded. 



THE WORK OF LUTHER BURBANK 



Doubtless the greatest practical demonstrator of 

 the truth of the Darwinian theories of heredity is Mr. 

 Luther Burbank, the famous developer of new vari- 

 eties of plants. Mr. Burbank's work, which began 

 when he was a young man in New England, and 

 which has been carried on for the past forty odd 

 years at Santa Rosa, California, has included practical 

 experiments with hundreds of species of plants, the 

 number of his carefully gauged and recorded experi- 

 ments running into the hundreds of thousands. 



Every one has heard more or less of the results 

 achieved by this wizard among plant experimentors. 

 His first important results were obtained with the 

 potato, which he raised from the seed, thereby pro- 



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