Origin of Species Variorum

→ parts of the world, 1859 1860 1861 1866 1869

regions, 1872

→ occur in the same order 1869 1872

are similarly absent 1859 1860 1861

are similarly placed 1866

yet seldom perceived by us, the whole economy of nature will be utterly obscured. Whenever we can precisely say why this species is more abundant in individuals than that; why this species and not another can be naturalised in a given country; then, and not

till

until

then, we may justly feel surprise why we cannot account for the extinction of

this

any

particular species or

group

any group

of species.

the

Forms

Life

changing

almost

simultaneously

throughout

the

World .—

World. —

World.

World .

Scarcely any palæontological discovery is more striking than the fact, that the forms of life change almost simultaneously throughout the world. Thus our European Chalk formation can be recognised in many distant →parts of the world, under the most different climates, where not a fragment of the mineral chalk itself can be found;

namely

namely,

in North America, in equatorial South America, in Tierra del Fuego, at the Cape of Good Hope, and in the peninsula of India. For at these distant points, the organic remains in certain beds present an unmistakeable

degree of

....

resemblance to those of the Chalk. It is not that the same species are met with; for in some cases not one species is identically the same, but they belong to the same families, genera, and sections of genera, and sometimes are similarly characterised in such trifling points as mere superficial sculpture.

Moreover

Moreover,

other forms, which are not found in the Chalk of

Europe,

Europe

but which occur in the formations either above or below, →occur in the same order at these distant points of the world. In the several successive palæozoic formations of Russia, Western

Europe

Europe,

and North America, a similar parallelism in the forms of life has been observed by several