THE CREATION OF SPECIES 



he is aiming than did either of the original parents. 

 Nevertheless, if he sow the seeds of these hybrids 

 he may look forward with confidence to the appear- 

 ance of the dwarf green. And owing to the recessive 

 nature of both greenness and dwarfness, he can be 

 certain for further generations the dwarf greens thus 

 produced will come true to type. The green dwarfs 

 are all fixed as soon as they appear, and will throw 

 neither tails nor yellows. The less the hybrid re- 

 sembles the form at which the breeder aims, the 

 more likely is that form to breed true when it ap- 

 pears in the next generation." 



PRACTICAL APPLICATION OF MENDEL*S LAW 



Mendel's experiments and discoveries were made 

 as early as 1863. But no one knew of his work until 

 the rediscovery of the essential facts was made by 

 Professor Hugo de Vries of Amsterdam about the 

 year 1900. Professor de Vries may be said to have 

 discovered Mendel, sixteen years after the abbot's 

 death. Largely through the championship of the 

 famous Amsterdam botanist, the new theory of 

 heredity, which came to be known as Mendelism, 

 made its way rapidly. 



A host of biologists prominent among whom in 

 this country were Professor Jacques Loeb, now of 

 the Rockefeller Institute, and Professor Castle of 

 Harvard undertook experiments that are calculated 

 to test the new theories of heredity from many an- 

 gles, and a great variety of corroborative evidence 

 was soon in hand. It is essential that any one who 

 would understand the bearing of the laws of hered- 



195 



