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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1860
1861
1866
1869
1872

→ abortion of parts 1859 1860 1861 1866
partial or complete abortion 1869 1872
→ been attributed by some authors to pressure, and the shape 1859 1860 1861 1866
been attributed by some authors to the pressure 1869
sometimes been attributed to the pressure 1872
→ seeds in the ray-florets in some Compositæ countenances this idea; but, in the case 1859 1860 1861 1866
involucra on the florets, or to their mutual pressure, and the shape 1869 1872
→ corolla of 1859 1860 1861 1866
seeds in the ray-florets of some Compositæ countenances this idea; but with 1869 1872
→ that the inner and outer flowers 1859 1860 1861 1866
which 1869 1872
→ differ. 1859 1860 1861 1866
differ in their inner and outer flowers. 1869 1872
→ certain other parts of the flower had 1859 1860 1861 1866
the reproductive organs had 1869
the reproductive organs 1872
→ in 1859 1860 1861 1866
this can hardly be the sole cause, for in 1869 1872
→ there is a difference in 1859 1860 1861 1866
OMIT 1869 1872
→ oftenest 1859 1860
said to be oftenest 1861 1866
most 1869 1872
→ and become regular. 1859 1860 1861 1866
that is they become symmetrical. 1869
that is to become abnormally symmetrical. 1872
→ and of 1859 1860 1861 1866 1869
fact, and as 1872
→ I have recently observed in some garden pelargoniums, that 1859 1860 1861 1866
I have recently observed in many pelargoniums, that 1869
in many pelargoniums, the two upper petals in 1872
→ often loses the patches of darker colour in the two upper petals; and that 1859 1860 1861
often loses the patches of darker colour in the two upper petals; and that, 1866
the two upper petals often lose their patches of darker colour; and 1869
often lose their patches of darker colour; and 1872
→ when the 1859 1860 1861 1866
When the 1869
the central flower thus becoming peloric or regular. When the 1872
→ only 1859 1860 1861 1866
not quite aborted but is 1869 1872
→ of the central and exterior flowers of a head or umbel, I do not feel at all sure that C. c. 1859 1860 1861
of the central and exterior flowers of a head or umbel, I do not feel at all sure that c. c. 1866
in the central and exterior flowers, 1869
OMIT 1872
→ in 1859 1860 1861 1866
or necessary for 1869 1872
→ plants of these two orders, is so far-fetched, as it may at first appear: 1859 1860 1861
plants of these two orders, is so far-fetched as it may at first appear: 1866
these plants, is highly probable; 1869 1872
difference
between
in
the ray and central florets of, for instance, the daisy, and this difference is often accompanied with the →abortion of parts of the
reproductive organs.
flower.
But
But,
in some
of these
Compositous
plants, the seeds also differ in shape and
sculpture.
sculpture;
and
and
even
even
the
the
ovary
ovary
itself,
itself,
with
with
its
its
accessory
accessory
parts,
parts,
differs,
differs,
as
as
has
has
been
been
described
described
by
by
Cassini.
Cassini.
These differences have →been attributed by some authors to pressure, and the shape of the →seeds in the ray-florets in some Compositæ countenances this idea; but, in the case of the →corolla of the Umbelliferæ, it is by no means, as Dr. Hooker informs me,
the
in
species with the densest heads →that the inner and outer flowers most frequently →differ. It might have been thought that the development of the ray-petals by drawing nourishment from →certain other parts of the flower had
causes
caused
their abortion; but →in some Compositæ →there is a difference in the seeds of the outer and inner florets
differ without
differ, without
without
any difference in the corolla.
Possibly
Possibly,
these several
differ- ences
differences
may be connected with
the
some
different
difference
in the
in the
flow of nutriment towards the central and external flowers: we know, at least, that
with normally
with
in
irregular flowers, those nearest to the axis are →oftenest subject to peloria, →and become regular. I may add, as an instance of
this
this,
→and of a striking case of correlation, that →I have recently observed in some garden pelargoniums, that
in the
the
central flower of the
truss,
truss
→often loses the patches of darker colour in the two upper petals; and that when this occurs, the adherent nectary is quite
aborted.
aborted;
→when the colour is absent from only one of the two upper petals, the nectary is →only much shortened.
With respect to the
development of
difference in
the
corolla,
corolla
→of the central and exterior flowers of a head or umbel, I do not feel at all sure that C. c.
Sprengels
Sprengel's
idea that the ray-florets serve to attract insects, whose agency is highly advantageous →in the fertilisation of →plants of these two orders, is so far-fetched, as it may at first appear: