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Vries, Hugo de, 1848-1935

"Species and Varieties, Their Origin by Mutation"

These two forms were distinguished by
Linnaeus as different species, but have been considered by subsequent
writers as elementary species or so-called systematic varieties of one
species designated with the name of the presumably older type, the _O.
biennis_. Varietal differences in a physiologic sense they [257] do not
possess, and for this reason afford a pure instance of unbalanced union,
though differing in more than one point.
I have made reciprocal crosses, taking at one time the small-flowered
and at the other the common species as pistillate parent. These crosses
do not lead to the same hybrid as is ordinarily observed in analogous
cases; quite on the contrary, the two types are different in most
features, both resembling the pollen-parent far more than the
pistil-parent. The same curious result was reached in sundry other
reciprocal crosses between species of this genus. But I will limit
myself here to one of the two hybrids.
In the summer of 1895 I castrated some flowers of _O. muricata_, and
pollinated them with _O. biennis_, surrounding the flowers with paper
bags so as to exclude the visits of insects. I sowed the seeds in 1896
and the hybrids were biennial and flowered abundantly the next year and
were artificially fertilized with their own pollen, but gave only a very
small harvest.


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