1916] DEV RIES—DIMORPHIC MUTANTS 251 
on a sufficiently large scale, using the seeds produced by my pure 
strain of O. lata fertilized by O. Lamarckiana. The seeds.of 1909 
gave 564 seedlings, with 18 per cent /ata and 2 percent cana. Those 
of 1908 gave 1550 seedlings, 8 per cent of which were /ata and 9 per 
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Fic. 1.—Oenothera Lamarckiana mut. cana: a young plant showing the narrow 
leaves by which it is easily distinguished from rosettes of the Lamarckiana type in 
the same sowings; June 11, 1915. 
cent were cana. Other mutants appeared in these cultures in 
different proportions, as usual. 
Among the seeds of pure O. Lamarckiana, O. cana is much the 
rarer. In 1913 I fertilized, on 5 strong biennial specimens, almost 
all the flowers during two months and got sufficient seed to have 
20,000 seedlings in 1914. Of these only 6 were cana, giving a per- 
centage of 0.03 per cent. In the same boxes 7 rubrinervis and 5 
