Origin of Species Variorum

→ is familiar with 1872

knows 1859 1860 1861 1866 1869

→ partial or complete abortion 1869 1872

abortion of parts 1859 1860 1861 1866

→ sometimes been attributed to the pressure 1872

been attributed by some authors to pressure, and the shape 1859 1860 1861 1866

been attributed by some authors to the pressure 1869

→ involucra on the florets, or to their mutual pressure, and the shape 1869 1872

seeds in the ray-florets in some Compositæ countenances this idea; but, in the case 1859 1860 1861 1866

→ seeds in the ray-florets of some Compositæ countenances this idea; but with 1869 1872

corolla of 1859 1860 1861 1866

→ which 1869 1872

that the inner and outer flowers 1859 1860 1861 1866

→ differ in their inner and outer flowers. 1869 1872

differ. 1859 1860 1861 1866

→ the reproductive organs 1872

certain other parts of the flower had 1859 1860 1861 1866

the reproductive organs had 1869

→ this can hardly be the sole cause, for in 1869 1872

in 1859 1860 1861 1866

→ OMIT 1869 1872

there is a difference in 1859 1860 1861 1866

→ most 1869 1872

oftenest 1859 1860

said to be oftenest 1861 1866

→ that is to become abnormally symmetrical. 1872

and become regular. 1859 1860 1861 1866

that is they become symmetrical. 1869

→ fact, and as 1872

and of 1859 1860 1861 1866 1869

→ in many pelargoniums, the two upper petals in 1872

I have recently observed in some garden pelargoniums, that 1859 1860 1861 1866

I have recently observed in many pelargoniums, that 1869

→ often lose their patches of darker colour; and 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

→ the central flower thus becoming peloric or regular. When the 1872

when the 1859 1860 1861 1866

When the 1869

→ not quite aborted but is 1869 1872

only 1859 1860 1861 1866

→ OMIT 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

→ or necessary for 1869 1872

in 1859 1860 1861 1866

→ these plants, is highly probable; 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

→ so, 1869 1872

it be advantageous, 1859 1860 1861 1866

→ seeds, it seems impossible that their differences in shape, which are not always correlated with any difference in the 1869 1872

differences both in the internal and external structure of the seeds, which are not always correlated with any differences in the 1859 1860 1861

differences in the 1866

→ corolla, 1869 1872

flowers, it seems impossible that they 1859 1860 1861 1866

→ beneficial; 1872

advantageous to the plant: 1859 1860 1861 1866

beneficial: 1869

→ sometimes 1869 1872

in some cases, according to Tausch, 1859 1860 1861 1866

→ OMIT 1872

we see that 1859 1860 1861 1866

as before remarked, we see that 1869

→ variation and correlation, 1869 1872

correlated growth, and 1859 1860 1861 1866

difference between the outer and inner flowers in some Compositous and Umbelliferous plants. Every one →is familiar with the difference

between

the ray and central florets of, for instance, the daisy, and this difference is often accompanied with the →partial or complete abortion of the

flower.

reproductive organs.

But,

But

in some

Compositous

of these

plants, the seeds also differ in shape and

sculpture;

and

even

the

ovary

itself,

with

its

accessory

parts,

differs,

has

been

described

Cassini.

These differences have →sometimes been attributed to the pressure of the →involucra on the florets, or to their mutual pressure, and the shape of the →seeds in the ray-florets of some Compositæ countenances this idea; but with the Umbelliferæ, it is by no means, as Dr. Hooker informs me,

the

species with the densest heads →which most frequently →differ in their inner and outer flowers. It might have been thought that the development of the ray-petals by drawing nourishment from →the reproductive organs

caused

causes

their abortion; but →this can hardly be the sole cause, for in some Compositæ →OMIT the seeds of the outer and inner florets

without

differ without

differ, without

any difference in the corolla.

Possibly,

Possibly

these several

differ- ences

differences

may be connected with

some

the

difference

different

in the

....

flow of nutriment towards the central and external flowers: we know, at least, that

with normally

with

irregular flowers, those nearest to the axis are →most subject to peloria, →that is to become abnormally symmetrical. I may add, as an instance of

this,

this

→fact, and as a striking case of correlation, that →in many pelargoniums, the two upper petals in

in the

the

central flower of the

truss,

truss

→often lose their patches of darker colour; and when this occurs, the adherent nectary is quite

aborted.

aborted;

→the central flower thus becoming peloric or regular. When the colour is absent from only one of the two upper petals, the nectary is →not quite aborted but is much shortened.

With respect to the

difference in

development of

the

corolla

corolla,

→OMIT

Sprengels

Sprengel's

idea that the ray-florets serve to attract insects, whose agency is highly advantageous →or necessary for the fertilisation of →these plants, is highly probable; and if →so, natural selection may have come into play. But

in regard

with respect

to the →seeds, it seems impossible that their differences in shape, which are not always correlated with any difference in the →corolla, can be in any way →beneficial; yet in the Umbelliferæ these differences are of such apparent

importance —

importance—

the seeds being →sometimes orthospermous in the exterior flowers and cœlospermous in the central

flowers, —

flowers,—

that the elder De Candolle founded his main divisions