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Vries, Hugo de, 1848-1935

"Species and Varieties, Their Origin by Mutation"

It yielded last summer
(1903) as high a percentage as 65 of twisted individuals, many of them
repeating the monstrosity on several branches. After some occasional
observations _Gypsophila paniculata_ [409] seems to promise similar
results. On the other hand I have sowed in vain the seeds of twisted
specimens of the soapwort and the cleavewort (_Saponaria officinalis_
and _Galium Aparine_). These and some others seem to belong to the same
group as the valerian and to constitute only poor or so-called
half-races.
Next to the torsions come the fasciated stems. This is one of the most
common of all malformations, and consists, in its ordinary form, of a
flat ribbon-like expansion of the stems or branches. Below they are
cylindrical, but they gradually lose this form and assume a flattened
condition. Sometimes the rate of growth is unequal on different portions
or on the opposite sides of the ribbon, and curvatures are produced and
these often give to the fasciation a form that might be compared with a
shepherd's crook. It is a common thing for fasciated branches and stems
to divide at the summit into a number of subdivisions, and ordinarily
this splitting occurs in the lower part, sometimes dividing the entire
fasciated portion. In biennial species the rosette of the root-leaves of
the first year may become changed by the monstrosity, the heart
stretching in a transverse direction so as to become linear.


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