1922] Setchell-Goodspeed-Clausen: Nicotiana Tahacum 481 



was pink and the leaves were more slightly attenuate at the base. 

 F.J, 12F3H^P33P3s, gave 25 plants, 13 of which had the sessilifolia 

 leaf of type 18 ; 7, auriculata of type 10 ; and 5, auriculata of type 8. 

 In flower color. 17 were some shade of pink and 8 red. The line was 

 not grown in further generations. 



Type 20 was not selected for illustration in F,, but was a plant 

 chosen because of its very close resemblance to macrophylla, coming 

 even closer than type 16. The F3, I2F3H4P40P44) consisted of 25 vig- 

 orous plants of remarkable uniformity. In height, habit, inflorescence, 

 flower, color, shape, fruit, etc., the details follow those of macrophylla 

 so closely as to be indistinguishable unless possibly by careful and labor- 

 ious biometric study. This type may represent a practically pure 

 recombination equivalent to macrophylla, and is to be compared and 

 contrasted with type 15. 



In 1913 two families of F^, one of 21 plants and the other of 100 

 plants, were uniform, as were 3 families of 50 plants each of F- in 

 1914. ■ In 1914, however, a surprising thing happened. A fourth 

 family of Fg, consisting of 50 plants, was uniform except one plant 

 which had pink (instead of red) flowers and an auriculata leaf ap- 

 proximating type 8 or 10. It seems certain that this plant must have 

 been an intruder, but its seed was saved under bag and grown and is 

 noted below and on the pedigree chart as type 20a. The other 3 plants 

 of F5 whose seed was sown in 1915 gave type 20 in Fg in families of 

 10, 9, and 8 respectively, and in turn the seed of 4 individuals of 

 "pure" type 20 gave, in 1916, uniformity in families of 10 each. 



Type 20a, which originated or intruded in 1914, in one plant of 

 F5 of type 20 gave in Fq, in 1915, 10 plants segregating for flower 

 color and probably also for leaf characters, although the notes taken 

 are inconclusive on the latter point. In 1916 F. of 10 good plants 

 showed uniformly red flowers, but 7 had sessilifolia leaves, 4 of which 

 were decidedly contracted at the base and 3 had very short winged 

 petioles (auriculata of type 8 or type 10). On the whole it seems 

 most likely that the single plant in the F^ family was an intruder, 

 since all other families of the line have been constant since F,. A stray 

 seed somewhere along the processes of culture would explain it and 

 its appearance is all the more incomprehensible as a matter of inclu- 

 sion in the pedigree of type 20, as it is so close to macrophylla as to 

 seem practically identical with it. 



