" They are of very rare occurrence and are to be
considered as sudden and definite steps.
Lastly, we have to consider those varieties, which vary in a much wider
range than the ordinary ones, and seem to fluctuate between two opposite
extremes, as for instance variegated leaves, cultivated varieties with
variegated or striped flowers, double flowers and some other anomalies.
They are eversporting and ever-returning from one type to the other. If
however, we take the group of these extremes and their intermediates as
a whole, this group remains constant during the succeeding generations.
Here we find once more an instance of the seemingly contradictory
combination of high variability and absolute constancy. It means that
the range of variability has quite definite limits, which in the common
course of things, are never transgressed.
We may infer therefore that the word variability has such a wide range
of meanings that it ought never be used without explanation. [192]
Nothing indeed, is more variable than the signification of the term
variable itself.
For this reason, we will furthermore designate all variations under the
influence of neighbors with the new and special term "vicinism." It
always indicates the result of crossing.
Leaving this somewhat lengthy terminological discussion, we now come to
the description of the phenomenon itself.
Pages:
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199