Striped Flowers 317 



from striped to red and frora red to stripes, oc- 

 cur by seed, even by the strictest exclusion of 

 cross-fertilization. As far as my experiments 

 go, they are the rule, and parent-plants that 

 do not give such reversions, at least in some of 

 their offspring, are very rare, if not wholly 

 wanting. Bud-variations and variations within 

 the spike I have as yet only observed on the 

 striped individuals, and never on the red ones, 

 though I am confident that they might appear in 

 larger series of experiments. Both cases are 

 more common on individuals with broad stripes 

 than on plants bearing only the narrower red 

 lines, as might be expected, but even on the al- 

 most purely yellow individuals they may be seen 

 from time to time. Bud-variations produce 

 branches with spikes of uniform red flowers. 

 Every bud of the plant seems to have equal 

 chances to be transformed in this way. Some 

 striped racemes bear a few red flowers, which 

 ordinarily are inserted on one side of the spike 

 only. As they often cover a sharply defined 

 section of the raceme, this circumstance has 

 given rise to the term of sectional variability to 

 cover such cases. Sometimes the section is 

 demarcated on the axis of the flower-spike by a 

 brownish or reddish color, sharply contrasting 

 with the green hue of the remaining parts. 

 Sectional variation may be looked at as a 



