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Vries, Hugo de, 1848-1935

"Species and Varieties, Their Origin by Mutation"

Duchesne's definition was evidently a sharp and useful one,
since it developed for the first time the idea of latent or dormant
qualities, [186] formerly active, and awaiting probably through
centuries an occasion to awaken, and to display the lost characters.
Cases of apparent reversion were often seen in nurseries, especially in
flower culture, which under ordinary circumstances are rarely wholly
pure, but always sport more or less into the colors and forms of allied
varieties. Such sporting individuals have to be extirpated regularly,
otherwise the whole variety would soon lose its type and its uniformity
and run over to some other form in cultivation in the vicinity. For this
reason atavism in nurseries causes much care and labor, and consequently
is to be dealt with as a very important factor.
From time to time the idea has suggested itself to some of the best
authorities on the amelioration of plants, that this atavism was not due
to an innate tendency, but, in many cases at least, was produced by
crosses between neighboring varieties. It is especially owing to Verlot
that this side of the question was brought forward. But breeders as a
rule have not attached much importance to this supposition, chiefly
because of the great practical difficulties attending any attempt to
guard the species of the larger cultures against intermixture with other
varieties.


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