Origin of Species Variorum

→ to the various 1869 1872

various 1859 1860 1861 1866

→ a single birthplace is the 1869 1872

this has been the universal 1859 1860 1861 1866

→ must on our theory all be 1872

on my theory have all 1859 1860 1861 1866

must on the theory all be 1869

→ OMIT 1869 1872

some part of 1859 1860 1861 1866

→ some one area. 1869 1872

the area inhabited by their progenitor. 1859 1860 1861 1866

→ If, when 1872

If it can be shown to be almost invariably the case, that a region, of which 1859 1860 1861 1866

When 1869

→ OMIT 1869 1872

its inhabitants are closely related to, or belong to the same genera with 1859 1860 1861

its inhabitants are closely related to, or belong to the same genera with, 1866

→ inhabiting one region are different from those of 1869 1872

of a second region, has probably received at some former period immigrants from this 1859 1860 1861 1866

→ though closely allied to them, it can be shown that migration from the one region to the other has probably occurred at some former period, our general view will be much strengthened; for the explanation is obvious on the principle of descent with modification. 1872

my theory will be strengthened; for we can clearly understand, on the principle of modification, why the inhabitants of a region should be related to those of another region, whence it has been stocked. 1859 1860 1861 1866

but are closely allied or belong to the same genera, if in all such cases it can be shown that there probably has been at some former period migration from the one region to the other, our general view will be much strengthened; for the explanation is obvious on the principle of descent with modification. 1869

→ the species of 1869 1872

species in 1859 1860 1861 1866

→ OMIT 1869 1872

(by substituting the word variety for species) 1859 1860 1861 1866

→ OMIT 1869 1872

in an ingenious paper 1859 1860 1861 1866

→ who 1869 1872

in which he 1859 1860 1861 1866

→ species." And it is now well known that he attributes this coincidence to descent with modification. 1872

species." 1859 1860 1866

species." 1861

species." And I now know that he attributes this coincidence to descent with modification. 1869

↑ 1 blocks not present in 1869 1872; present in 1859 1860 1861 1866

And I now know from correspondence, that this coincidence he attributes to generation with modification.

→ question of single or 1872

previous remarks on "single and 1859 1860 1866

previous remarks on "single and 1861

discussion on "single and 1869

→ creation differs from another though 1872

creation" do not directly bear on another 1859 1860 1866

creation" do not directly bear on another 1861

creation" does not directly bear on another 1869

→ must be 1869 1872

on my theory, must have 1859 1860 1861 1866

→ that have supplanted each other, but have never 1872

which will never have 1859 1860 1861

which can never have 1866

which have supplanted each other, but which have never 1869

→ of the same species; 1869 1872

but will have supplanted each other; 1859 1860 1861 1866

→ the same form will be 1872

each variety will have 1859 1860 1861 1866

the same variety will be 1869

→ OMIT 1869 1872

I believe that during the slow process of modification 1859 1860 1861 1866

→ same species inhabiting the same area will be 1869 1872

species will have been 1859 1860 1861 1866

from a single birthplace; then, considering our ignorance with respect to former climatal and geographical changes and →to the various occasional means of transport, the belief that →a single birthplace is the law, seems to me incomparably the safest.

In discussing this subject, we shall be enabled at the same time to consider a point equally important for us, namely, whether the several

distinct

....

species of a genus, which →must on our theory all be descended from a common progenitor, can have

migrated

migrated,

(undergoing

undergoing

modification during →OMIT their

migration)

migration,

from →some one area. →If, when most of →OMIT the species →inhabiting one region are different from those of

other

another

region, →though closely allied to them, it can be shown that migration from the one region to the other has probably occurred at some former period, our general view will be much strengthened; for the explanation is obvious on the principle of descent with modification. A volcanic island, for instance, upheaved and formed at the distance of a few hundreds of miles from a continent, would probably receive from it in the course of time a few colonists, and their descendants, though modified, would still be

plainly

....

related by inheritance to the inhabitants of

the

that

continent. Cases of this nature are common, and are, as we shall hereafter

more fully

....

see, inexplicable on the theory of independent creation. This view of the relation of →the species of one region to those

another, does not differ much →OMIT from that

lately

....

advanced →OMIT by Mr. Wallace, →who

concludes,

concludes

that

"every

species has come into existence coincident both in space and time with a pre-existing closely allied →species." And it is now well known that he attributes this coincidence to descent with modification. ↑

The →question of single or multiple centres of →creation differs from another though allied question,—

namely

namely,

whether all the individuals of the same species

have

are

descended from a single pair, or single hermaphrodite, or whether, as some authors suppose, from many individuals simultaneously created. With

those

....

organic beings which never

intercross

intercross,

(if

such

exist),

exist,

the

each

species,

species

→must be descended from a succession of

improved

modified

varieties, →that have supplanted each other, but have never blended with other individuals or

varieties,

varie- ties,

varieties

→of the same species; so that, at each successive stage of

modification

modification,

and improvement,

....

all the individuals of →the same form will be descended from a single parent. But in the

majority

great majority

of cases, namely, with all organisms which habitually unite for each birth, or which

often

occasionally

intercross, →OMIT the individuals of the →same species inhabiting the same area will be kept nearly uniform by intercrossing; so that many individuals will

have gone

on simultaneously changing, and the whole amount of