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EVOLUTION, GENETICS, AND EUGENICS 



"Lamarck's evening-primrose" (Fig. 75), says De Vries, "is a 

 stately plant, with a stout stem, attaining often a height of 1.6 meters 

 and more. When not crowded the main stem is surrounded by a large 



Fig. 75. — Oenothera lamarckiana, the original type used by De Vries in his 

 experiments. This is the stock from Hilversum, from which arose in successive 

 generations a series of mutants. (From De Vries.) 



