No. 624] BLOSSOM COLOR INHERITANCE IN TOBACCO 83 



a perfect dominance as in the cross Carmine X Pink, for 

 the blossoms of the first generation plants are somewhat 

 paler than pure carmine. In the second generation there 

 is a segregation into whites, and various degrees of pinks 

 and reds, ranging from light pink to pure carmine. Of 

 278 second generation plants of this cross, grown in 1917, 

 the blossom colors were grouped as follows: 



White 



Light pink 



Lighter than carmine 



Total 278 



It is evident that the recessive whites which were easily 

 determined approximated very closely the theoretical 25 

 per cent. Owing, however, to the uncertainty of analyz- 

 ing correctly the varied pinks and reds, the carmines 

 which probably represent the homozygous dominants 

 are somewhat below the theoretical 25 per cent. It is 

 quite probable that this class is somewhat smaller than 

 it should be, owing to the difficulty of distinguishing with 

 certainty all the homozygous carmines from the hetero- 

 zygous somewhat paler carmines. 



A number of extracted, recessive whites of the second 

 generation of this cross have been grown and all have 

 produced white-blossomed progenies. These white-blos- 

 somed plants have proved somewhat puzzling, however, 

 for some seemed to reveal a hint of color, like an almost 

 imperceptible sheen, that could be detected only in cer- 

 tain lights. So fugacious was this suggestion of color, 

 that I felt inclined to ascribe it to the imagination, until 

 certain crosses were made with pink-flowered varieties 

 as follows : 



From the cross Pink (Maryland Mammoth) $ X White 

 (extracted) t^, 54 first generation plants w^ere obtained, of 

 which 17 were carmine, 18 wore pink as in tlio Mammoth, 

 and 19 somewhat lighter than carmnio. 



In the reciprocal of this erosr^, /. r.. Wlii1(> ( oxtraeted) 

 $ X Pink (Md. Mammoth) d^, 4:] pliintA wciv obtained, of 



