MENDEL’S METHOD 19 
Of even greater interest, however, are the more 
strictly experimental researches which have been pub- 
lished within the last five or six years. In the first 
place, we have the observations of de Vries, who has 
introduced anew method of study—that of cultivating 
great numbers of seedling plants with the object of 
discovering definite new forms or mutations among 
their number. Lastly, and in its results much 
the most important of all, we have the method of 
Mendel, published half a century ago, but only re- 
‘cently brought into prominence owing to its redis- 
covery and confirmation by three independent workers 
—Correns, Tschermak, and de Vries. This method 
consists in the cross breeding of strains of plants or 
animals which differ in definite characters, and in the 
statistical examination of the proportions in which 
these characters appear among the offspring obtained 
from the crosses. 
Further experiments on the lines which Mendel in- 
dicated bid fair to revolutionize within a few years the 
arts of the breeders of plants and animals. This is 
due to the fact that such experiments are leading to 
the introduction into these pursuits of a degree of 
scientific exactness which was previously altogether 
unforeseen. The change in our ideas regarding the 
method of hereditary transmission of characters, which 
has resulted from these experiments, has been aptly 
compared with the change brought about in men’s 
understanding of the science of chemistry by 
Dalton’s conception of the atom. For the rest the 
new experiments tend on the whole to confirm the 
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