A FEW OLD FAVORITES 129 



test his knowledge of the principles of heredity 

 to the utmost, and at the same time will give him 

 definite ideas about the practicalities of plant 

 development that will be at once interesting and 

 valuable. 



Meantime the experimenter may introduce 

 problems of far greater complexity if he so de- 

 sires by combining larger numbers of the plants 

 somewhat at random, allowing them to be cross- 

 fertilized by the bees. In this way he may 

 secure, as I have done in some experiments, 

 columbines of the most wonderful variety. In 

 some of the mixed hybrid colonies the blending 

 of hereditary factors was so complex that among 

 ten thousand plants there would be perhaps not 

 five hundred that could be classified as approxi- 

 mately identical with one another, or as conform 

 ing to a specific type. 



In other words, there would be perhaps nine 

 thousand five hundred individual plants, each 

 of which might be said to constitute a distinct 

 variety. 



In the course of these experiments there were 

 made perhaps ten thousand careful hand-pol- 

 linations between different specimens of these 

 variant hybrids, and, needless to say, plants 

 were secured with exceptional blossoms of 

 many kinds. 



Vol 7— Bur. £ 



