THE CREATION OF SPECIES 



known as the Evening Primrose, a plant familiar as 

 a roadside weed in the United States, where it is in- 

 digenous. The specimens growing in the fields near 

 Amsterdam are the descendants of plants originally 

 brought from America. 



It would appear that the evening primrose has a 

 peculiar and characteristic propensity to vary in 

 type; and it is probable that this propensity to vary 

 has been accentuated by some obscure influence of 

 changed nutritional conditions due to the European 

 soil. In any event, Professor de Vries observed that 

 plants seemingly the offspring of the same parent 

 plant, differ very widely among themselves. 



Gathering seed and experimenting in his botanical 

 garden.at Amsterdam, De Vries was able to develop, 

 in the course of successive generations, no fewer than 

 twelve races of evening primrose from a common 

 stock. 



The experiments involved the planting of many 

 thousands of seeds with elaborate precautions against 

 cross-fertilization. But the results' were unequivocal. 

 A dwarf form of evening primrose might be the off- 

 spring of a giant form; and the dwarf, sprung into 

 being in a single generation, would breed true. 



In other words, a new race, differing so widely 

 from the old that it might justly be termed a new 

 species, was observed to develop in a single genera- 

 tion. Thus the necessity for assuming that evolution 

 has proceeded only through the natural selection of 

 minute variations, was done away with. It was made 

 clear that Nature might supply by mutation widely 

 divergent types through which natural selection 



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