I must not be content with proposing this new conception, but must give
the facts on which this assumption rests. These facts are the results of
simple experiments, which nevertheless are by no means easy to carry
out, as they require the utmost care to secure the absolute purity of
the seeds that are employed. This can only be guaranteed by previous
cultures of isolated plants or groups of plants, or by artificial
pollination.
[200] Once sure of this preliminary condition, the experiment simply
consists in growing a variety at a given distance from its species and
allowing the insects to transfer the pollen. After harvesting the seed
thus subjected to the presumed cause of the impurities, it must be sown
in quantities, large enough to bring to light any slight anomaly, and to
be examined during the period of blooming.
The wild seashore aster, _Aster Tripolium_, will serve as an example. It
has pale violet or bluish rays, but has given rise to a white variety,
which on testing, I have found pure from seed. Four specimens of this
white variety were cultivated at a distance of nearly 100 meters from a
large lot of plants of the bluish species. I left fertilization to the
bees, harvested the seeds of the four whites separately and had from
them the following year more than a thousand flowering plants.
Pages:
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207