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GENERAL BIOLOGY 



wild plants from a field near Amsterdam and culti- 

 vated the stock in his garden for eight generations. 

 He began with nine plants, from the matured seeds 

 of which, two years later (since the plant is a bien- 

 nial), he grew some 15,000 plants. Ten of these 

 were of a different appearance from the rest, and these 

 he carefully segregated. Five of them were dwarf, 

 with small leaves but full-sized flowers, and these 

 he named nanella; the other five had broad leaves 

 and a luxuriant growth, and the flowers were all 

 pistillate, and hence could not produce seed, except 

 when crossed with another variety ; this form he 

 called lata. Both nanella and lata were found there- 

 after in every culture from lamarckiana seed, until 

 the seventh generation, and in every case, when self- 

 fertilized, the former " bred true." In the third 

 generation a new form appeared which he called 

 rubrinervis, and in the next, three others, oblonga, 

 albida, and gigas. The first was characterized by 



MUTATIONS OF (Enothera lamarckiana (FROM DE VRIES) 



