86 



NEW DIMORPHIC MUTANTS OF THE OENOTHERAS. 



sum. It was only recognized at the end of July, when it opened its 

 first flowers. It yielded few seeds, which gave rise to 19 seedlings 

 only, all of which flowered in 1914. Of these, 13 exactly duplicated 

 the type of 0. Lamarckiana, 5 were cana, and one was a mutant 

 nanella. These figures point to a percentage of 26 per cent cana. 

 0. cana from lata no. 1.— From the first mutant of 1906-1907, 

 previously described, I have derived a pedigree family in order 

 to try its constancy and got the following result: 



1906-1907 Mutant Mutant 



1912 Second generation 16 per cent cana Lamarckiana 



1913 Third generation 24-34 per cent cana Lamarckiana Lamarckiana 



The size of these cultures is given in table I. 



Table I. 



The offspring of two cana individuals of the second generation 

 have been studied separately, as well as those of one specimen of 

 the Lamarckiana type. The plants have been under observation 

 through their whole lifetime, so far as space allowed, the numbers 

 of the flowering individuals being given in the column next to that 

 of the totals. The cana were all of the same type ; the Lamarckiana 

 exactly repeated the marks of the original species. Three of the 

 dwarfs have flowered. They all had the marks of ordinary 0. La- 

 marckiana mut. nanella and none of those of 0. cana. This has 

 been the case in some of the other pedigree cultures of this type, 

 but it should be remarked that in other cases the characters of 

 0. cana may combine with the dwarf stature. Such dwarfs have 

 the narrow gray foliage and are easily distinguished from typical 

 0. nanella specimens. 



The self-fertilized seeds of the cana individuals split in both 

 generations into cana and Lamarckiana, just as 0. scintillans splits 

 into scintillans and Lamarckiana. The proportions 16-24-34 



