and white varieties
...OMIT 1869 1872 |
of the same species of Verbascum when 1859 1860 1861 1866 |
when crossed when crossed 1869 1872 | intercrossed 1859 1860 1861 1866 |
produce less
seed seed 1869 1872 | seed, 1859 1860 1861 1866 |
than
the similarly the similarly 1869 1872 | do either 1859 1860 1861 | does either 1866 |
coloured
varieties varieties 1859 1860 1861 1869 1872 | variety 1866 |
of the same species. of the same species. 1869 1872 |
when fertilised with pollen from their own coloured flowers. 1859 1860 1861 |
when fertilised with pollen from its own coloured flowers. 1866 |
Moreover, he asserts
that, that, 1866 1869 1872 | that 1859 1860 1861 |
when yellow and white varieties of one species are crossed with yellow and white varieties of a
distinct
species, more seed is produced by the crosses between the
similarly similarly 1860 1861 1866 1869 1872 | same 1859 |
coloured flowers, than between those which are differently coloured. Mr.
Scott,
also,
has experimented on the species and varieties of Verbascum; and although unable to confirm
Gärtners Gärtners 1869 | Gärtner's 1872 |
results on the crossing of the distinct species, he finds that the dissimilarly coloured varieties of the same species yield fewer seeds, in the proportion of 86 to 100, than the similarly coloured varieties. Yet these varieties
differ in no respect except in the differ in no respect except in the 1869 1872 |
of Verbascum present no other difference besides the mere 1859 1860 1861 1866 |
colour of
their their 1869 1872 | the 1859 1860 1861 1866 |
flowers; flowers; 1869 1872 | flower; 1859 1860 1861 1866 |
and one variety can sometimes be raised from the seed of
....... 1869 1872 | the 1859 1860 1861 1866 |
another. another. 1869 1872 | other. 1859 1860 1861 1866 |
↑1 blocks not present in 1866 1869 1872; present in 1859 1860 1861 | From observations
which I have made on certain varieties of hollyhock, I am inclined to suspect that they present analogous facts.
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Kölreuter, whose accuracy has been confirmed by every subsequent observer, has proved the remarkable fact, that one
particular variety particular variety 1869 1872 | variety 1859 1860 1861 1866 |
of the common tobacco
was was 1869 1872 | is 1859 1860 1861 1866 |
more
fertile fertile 1869 1872 | fertile, 1859 1860 1861 1866 |
than the other varieties, when than the other varieties, when 1869 1872 |
when 1859 1860 1861 1866 |
crossed with a widely distinct
species. species. 1869 1872 | species, 1859 1860 1861 1866 |
....... 1869 1872 | than 1859 1860 1861 1866 |
....... 1869 1872 | are 1859 1860 1861 1866 |
....... 1869 1872 | the 1859 1860 1861 1866 |
....... 1869 1872 | other 1859 1860 1861 1866 |
....... 1869 1872 | varieties. 1859 1860 1861 1866 |
He
experimented experimented 1861 1866 1869 1872 | experimentised 1859 1860 |
on five
forms, forms, 1859 1860 1861 1866 1869 | forms 1872 |
which are commonly reputed to be varieties, and which he tested by the severest trial, namely, by reciprocal crosses, and he found their mongrel offspring perfectly fertile. But one of these five varieties, when used either as
the father the father 1869 1872 | father 1859 1860 1861 1866 |
or mother, and crossed with the Nicotiana glutinosa, always yielded hybrids not so sterile as those which were produced from the four other varieties when crossed with N.
glutinosa. glutinosa. 1859 1860 1866 1869 1872 |
glutinosa. Hence the reproductive system of this one variety must have been in some manner and in some degree modified. 1861 |
Hence the reproductive system of this one variety must have been in some manner and in some degree modified. |
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From these
facts facts 1869 1872 | facts; 1859 1860 1861 1866 |
it cannot be maintained that varieties when crossed are invariably quite fertile;—from it cannot be maintained that varieties when crossed are invariably quite fertile;—from 1869 |
from 1859 1860 1861 1866 |
it can no longer be maintained that varieties when crossed are invariably quite fertile. From 1872 |
the great difficulty of ascertaining the infertility of varieties in a state of nature, for a supposed
variety, variety, 1866 1869 1872 | variety 1859 1860 1861 |
if
proved to be infertile proved to be infertile 1866 1869 1872 |
infertile 1859 1860 1861 |
in any
degree, degree, 1866 1869 1872 | degree 1859 1860 1861 |
would
almost universally almost universally 1866 1869 1872 | generally 1859 1860 1861 |
be ranked as
a species;—from man attending only to a species;—from man attending only to 1869 |
species; from man selecting only 1859 1860 1861 |
a species; from man selecting only 1866 |
a species;— from man attending only 1872 |
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