Origin of Species Variorum

→ slowly to come 1869 1872

to come slowly 1859 1860 1861 1866

→ the inhabitants of the north, they 1869

arctic beings and ill-fitted for their former more temperate inhabitants, the latter would be supplanted and arctic productions 1859 1860 1861 1866

the inhabitants of the north, these 1872

→ places of the former inhabitants of the temperate regions. 1869 1872

places. 1859 1860 1861 1866

→ latter, 1869 1872

inhabitants of the more temperate regions would 1859 1860 1861 1866

→ would travel further and further 1869 1872

travel 1859 1860 1861 1866

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

We may suppose that the Glacial period came on a little earlier or later in North America than in Europe, so will the southern migration there have been a little earlier or later; but this will make no difference in the final result.

→ as the warmth increased and the snow still further disappeared, higher and higher, 1866 1869 1872

higher and higher, as the warmth increased, 1859 1860 1861

→ together in a body 1866 1869

in a body together 1859 1860 1861

together 1872

→ European and North American lowlands, would again be found in the arctic regions of the Old and New Worlds, 1869 1872

lowlands of the Old and New Worlds, 1859 1860 1861

European and North American lowlands, 1866

→ and on many isolated mountain-summits far distant from each other. 1869 1872

would be left isolated on distant mountain-summits (having been exterminated on all lesser heights) and in the arctic regions of both hemispheres. 1859 1860 1861

would be found in the arctic regions of the Old and New Worlds, and isolated on many mountain-summits far distant from each other, having been exterminated on all lesser heights. 1866

follow the changes more readily, by supposing a new glacial period →slowly to come on, and then pass away, as formerly occurred. As the cold came on, and as each more southern zone became fitted for →the inhabitants of the north, they would take

their

the

→places of the former inhabitants of the temperate regions. The →latter, at the same

time

time,

→would travel further and further southward, unless they were stopped by barriers, in which case they would perish. The mountains would become covered with snow and ice, and their former Alpine inhabitants would descend to the plains. By the time that the cold had reached its maximum, we should have

a uniform

arctic fauna and flora, covering the central parts of Europe, as far south as the Alps and Pyrenees, and even stretching into Spain. The now temperate regions of the United States would likewise be covered by arctic plants and

animals

animals,

and these would be nearly the same with those of Europe; for the present circumpolar inhabitants, which we suppose to have everywhere travelled southward, are remarkably uniform round the world. ↑

As the warmth returned, the arctic forms would retreat northward, closely followed up in their retreat by the productions of the more temperate regions. And as the snow melted from the bases of the mountains, the arctic forms would seize on the cleared and thawed ground, always

ascending

ascending,

→as the warmth increased and the snow still further disappeared, higher and higher, whilst their brethren were pursuing their northern journey. Hence, when the warmth had fully returned, the same

arctic

....

species, which had lately lived →together in a body on the →European and North American lowlands, would again be found in the arctic regions of the Old and New Worlds, →and on many isolated mountain-summits far distant from each other.

Thus we can understand the identity of many plants