90 



NEW DIMORPHIC MUTANTS OF THE OENOTHERAS. 



following year (1914) I sowed the seeds of these 6 lots separately. 

 I counted the seedlings in the stage shown in fig. 1 without trans- 

 planting them. The cana were easily distinguished from the 

 Lamarckiana by their narrower leaves and gray color. There were 

 a number of dwarfs, which combined with this character those of 

 cana and will be called cana-nanella. 1 have planted them out 

 after finishing the countings and found them true dwarfs of the 

 cana type. About a dozen of them flowered as annuals, and some 

 flowered the following year as biennials. The result of the count- 

 ings is given in table III. 



The means for the whole plant are 34, 6 and 40 per cent. It is 

 easily seen that the deviations from the means fall within the 

 limits of ordinary chance, although all the seeds from the 10 cap- 

 sules of each group have been sown. Thus it is clear that the first 

 and the last fruits of a spike and those of a side branch may give 

 the same percentage figures of specimens of the parental type. 

 Moreover, the mean value is not essentially different from the 

 means of the pedigrees, as just given, which was 33 per cent. We 

 may conclude, therefore, that the mean percentage for all my 

 annual cultures is about 30-40. 



In order to compare the influence of biennial culture upon this 

 figure, I chose three healthy and very vigorous rosettes of 1913 and 

 kept them through the winter under glass. They had been reared 

 from seeds of a biennial mutant belonging to the group of cana 

 mutants from lata, from which pedigrees no. 2 and no. 3 were 

 derived ; but this special culture stayed in the rosette condition 

 during 1913. In 1914 three plants of the cana type became very 

 vigorous, reaching about double the height of the annual plants 

 and growing up to more than 2.5 m. Their stems also had twice 

 the thickness of the others, the foliage and flower spikes were very 



