Comparison with 1866 |
|
thirteen flowers of the one with the
pollen of the other; but only a single head produced any seed, and this one head produced only five grains. Manipulation in this
case case 1859 1860 1866 1869 1872 | ease 1861 |
could not have been injurious, as the plants have separated sexes. No one, I believe, has suspected that these varieties of maize are distinct species; and it is important to notice that the hybrid plants thus raised were themselves
perfectly
fertile; so that even Gärtner did not venture to consider the two varieties as specifically distinct. |
|
Girou de Buzareingues crossed three varieties of gourd, which like the maize has separated sexes, and he asserts that their mutual fertilisation is by so much the less easy as their differences are greater. How far these experiments may be trusted, I know not; but the forms experimentised
on,
are ranked by
Sageret, Sageret, 1866 1869 1872 | Sagaret, 1859 1860 1861 |
who mainly founds his classification by the test of infertility, as
varieties, and Naudin has come to the same conclusion. varieties, and Naudin has come to the same conclusion. 1866 1869 1872 |
varieties. 1859 1860 1861 |
|
|
The following case is far more remarkable, and seems at first quite
incredible; but it is the result of an astonishing number of experiments made during many years on nine species of Verbascum, by so good an observer and so hostile a witness,
as Gärtner: namely,
that yellow
and white varieties of the same species of Verbascum when
intercrossed
produce less seed,
than
does either does either 1866 | do either 1859 1860 1861 | the similarly 1869 1872 |
coloured
variety variety 1866 | varieties 1859 1860 1861 1869 1872 |
when fertilised with pollen from its own coloured flowers. when fertilised with pollen from its own coloured flowers. 1866 |
when fertilised with pollen from their own coloured flowers. 1859 1860 1861 |
of the same species. 1869 1872 |
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 same
coloured flowers, than between those which are differently coloured. ↑1 blocks not present in 1859 1860 1861 1866; present in 1869 1872 | Mr. Scott,
also,
has experimented on the species and varieties of Verbascum; and although unable to confirm Gärtners
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 of Verbascum present no other difference besides the mere
colour of the
flower;
and one variety can sometimes be raised from the seed of the
other.
|
thirteen flowers of the one
with the with the 1859 1860 1861 1866 1869 | kind with 1872 |
pollen of the other; but only a single head produced any seed, and this one head produced only five grains. Manipulation in this
ease ease 1861 | case 1859 1860 1866 1869 1872 |
could not have been injurious, as the plants have separated sexes. No one, I believe, has suspected that these varieties of maize are distinct species; and it is important to notice that the hybrid plants thus raised were themselves
perfectly
fertile; so that even Gärtner did not venture to consider the two varieties as specifically distinct. |
|
Girou de Buzareingues crossed three varieties of gourd, which like the maize has separated sexes, and he asserts that their mutual fertilisation is by so much the less easy as their differences are greater. How far these experiments may be trusted, I know not; but the forms
experimented experimented 1861 1866 1869 1872 | experimentised 1859 1860 |
on on 1861 1866 1869 1872 | on, 1859 1860 |
are ranked by
Sagaret, Sagaret, 1859 1860 1861 | Sageret, 1866 1869 1872 |
who mainly founds his classification by the test of infertility, as
varieties. varieties. 1859 1860 1861 |
varieties, and Naudin has come to the same conclusion. 1866 1869 1872 |
|
|
The following case is far more remarkable, and seems at first
quite quite 1859 1860 1861 1866 1869 | quite 1872 |
incredible; but it is the result of an astonishing number of experiments made during many years on nine species of Verbascum, by so good an observer and so hostile a
witness witness 1861 1866 1869 1872 | witness, 1859 1860 |
as Gärtner:
namely, namely, 1859 1860 1861 1866 1869 | namely 1872 |
that
yellow yellow 1859 1860 1861 1866 | the yellow 1869 1872 |
and white varieties
of the same species of Verbascum when of the same species of Verbascum when 1859 1860 1861 1866 |
OMIT 1869 1872 |
intercrossed intercrossed 1859 1860 1861 1866 | when crossed 1869 1872 |
produce less
seed, seed, 1859 1860 1861 1866 | seed 1869 1872 |
than
do either do either 1859 1860 1861 | does either 1866 | the similarly 1869 1872 |
coloured
varieties varieties 1859 1860 1861 1869 1872 | variety 1866 |
when fertilised with pollen from their own coloured flowers. when fertilised with pollen from their own coloured flowers. 1859 1860 1861 |
when fertilised with pollen from its own coloured flowers. 1866 |
of the same species. 1869 1872 |
Moreover, he asserts
that that 1859 1860 1861 | that, 1866 1869 1872 |
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. ↑1 blocks not present in 1859 1860 1861 1866; present in 1869 1872 | Mr. Scott,
also,
has experimented on the species and varieties of Verbascum; and although unable to confirm Gärtners
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
of Verbascum present no other difference besides the mere of Verbascum present no other difference besides the mere 1859 1860 1861 1866 |
differ in no respect except in the 1869 1872 |
colour of
the the 1859 1860 1861 1866 | their 1869 1872 |
flower; flower; 1859 1860 1861 1866 | flowers; 1869 1872 |
and one variety can sometimes be raised from the seed of
the the 1859 1860 1861 1866 | the 1869 1872 |
other. other. 1859 1860 1861 1866 | another. 1869 1872 |
|