THEORY AND PRACTICE 



ing. In the main discussion of Mendelian heredity 

 above, we have spoken as if the thing contem- 

 plated were the recombination of qualities that 

 are already patent in one parent or the other of 

 the original cross. But, in point of fact, the ob- 

 ject sought by the plant breeder often goes far 

 beyond the mere combination of existing quali- 

 ties, as the case of the blue poppy at once sug- 

 gests. 



The same thing is illustrated by a beautiful blue 

 gladiolus which Mr. Burbank developed by cross- 

 ing an imported gladiolus having a small purplish 

 flower with a large white one of his own develop- 

 ment. The mingling of hereditary factors here 

 gave new combinations, and ultimately produced 

 a large flower from which the obscuring pigments 

 had been removed, so that an underlying blue, 

 recessive to most other pigments, was revealed. 



It may be said that Mr. Burbank 's plant devel- 

 opments have, as a rule, been similarly carried 

 forward until qualities are so accentuated or modi- 

 fied as to seem of a quite different order from the 

 qualities of the parent forms. Here, for example, 

 is a giant amaryllis with a flower almost a foot 

 in diameter, the product of experiments in hy- 

 bridizing and selection that involved no parent 

 plant having a flower more than five or six inches 

 in diameter. Here is another hybrid amaryllis 

 bulb which puts forth a new bulblet every week, 

 fifty of them in a year, although the parent 

 forms from which this variety was developed were 

 accustomed to produce only half a dozen new bulb- 



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