And it is easily seen that this rule agrees
with that given above, and which was followed in my pedigree-culture.
Furthermore it is seen that there is a complete agreement between the
law of periodicity and the responses of the deviations to nourishment
and other conditions of life. Weak plants only produce low degrees of
deviation, the stronger the individual becomes, the higher it reaches in
the scale of differentiation, and the more often it develops leaves with
five or more blades. Whether weakness or strength are derived from outer
causes, or from the internal [365] succession of the periods of life, is
evidently of no consequence, and in this way the law of periodicity may
be regarded as a special instance of the more general law of response to
external conditions.
The validity of this law of periodicity is of course not limited to our
"five-leaved" clover. Quite on the contrary it is universal in
eversporting varieties. Moreover it may be ascertained and studied in
connection with the most widely different morphologic abnormalities, and
therefore affords easily accessible material for statistical inquiry. I
will now give some further instances, but wish to insist first upon the
necessity of an inquiry on a far larger scale, as the evidence as yet is
very scanty.
The great celandine (_Chelidonium majus_) has a very curious double
variety.
Pages:
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360