LUTHER BURBANK 



at night. This white canopy is really a modified 

 leaf and is called by the botanist a spathe. The 

 essential organs of the flower are distributed on 

 the central column called a spadix, and are ex- 

 ceedingly inconspicuous. The upper portion of 

 the spadix bears the pollen, and the lower portion 

 is the pistillate surface. But the two parts do 

 not mature at the same time, so self-fertilization 

 does not take place as would otherwise be in- 

 evitable. 



It has been found by experiment that the air 

 inside the tubular spathe is somewhat warmer 

 than the outside air. So it is not strange that 

 insects should gather here, and they naturally 

 come in contact with the pollen, and carry it to 

 other flowers that they subsequently visit. The 

 whiteness of the calla suggests that it is designed 

 to attract night-roving insects, the white flower 

 being more conspicuous at night than a brightly 

 colored one. 



MAKING A FBAGEANT CALLA 



It is not unlikely that some ancestors of the 

 calla depended on the bee for cross-fertilization, 

 and hence were fragrant. Otherwise it is hard 

 to account for the appearance in Mr. Burbank's 

 colony of callas of an individual that had a faint 

 but appreciable perfume. 



Whatever the explanation, such an anomaly did 

 appear a good many years ago, and Mr. Burbank 

 detected its presence and at once decided that this 



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