[553] The same holds good for _albida_, which appeared in 15 specimens,
or in 0.1%, of the whole culture. By careful cultivation these plants
proved not to be sickly, but to belong to a new, though weak type. It
was evident that I had already seen them in former years, but having
failed to recognize them had allowed them to be destroyed at an early
age, not knowing how to protect them against adverse circumstances. Even
this time I did not succeed in getting them strong enough to keep
through the winter.
Besides these, two new types were observed, completing the range of all
that have since been recorded to regularly occur in this family. They
were _scintillans_ and _gigas_. The first was obtained in the way just
described. The other hardly escaped being destroyed, not having showed
itself early enough, and being left in the bed after the end of the
selection. But as it was necessary to keep some rosettes through the
winter in order to have biennial flowering plants to furnish seeds, I
selected in August about 30 of the most vigorous plants, planted them on
another bed and gave them sufficient room for their stems and branches
in the following summer. Most of them sent up robust shoots, but no
difference was noted till the first flowers opened. One plant had a much
larger crown of bright blossoms than any of the others. [554] As soon as
these flowers faded away, and the young fruits grew out, it became clear
that a new type was showing itself. On that indication I removed all the
already fertilized flowers and young fruits, and protected the buds from
the visits of insects. Thus the isolated flowers were fertilized with
their own pollen only, and I could rely upon the purity of the seed
saved. This lot of seeds was sown in the spring of 1897 and yielded a
uniform crop of nearly 300 young _gigas_ plants.
Having found how much depends upon the treatment, I could gradually
decrease the size of my cultures. Evidently the chance of discovering
new types would be lessened thereby, but the question as to the repeated
production of the same new forms could more easily and more clearly be
answered in this way. In the following year (1896) I sowed half as many
seeds as formerly, and the result proved quite the same. With the
exception of _gigas_ all the described forms sprang anew from the purely
fertilized ancestry of normal _lamarckiana_s. It was now the fifth
generation of my pedigree, and thus I was absolutely sure that the
descendants of the mutants of this year had been pure and without
deviation for at least four successive generations.
Owing partly to improved methods of selection, [555] partly no doubt to
chance, even more mutants were found this year than in the former. Out
of some 8,000 seedlings I counted 377 deviating ones, or nearly 5%,
which is a high proportion. Most of them were _oblonga_ and _lata_, the
same types that had constituted the majority in the former year.
Public-domain text, read in full here on John Shaqi.
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