Origin of Species Variorum

→ first bed of the Silurian 1859 1860 1861 1866

Cambrian 1869 1872

→ We now know that animals, and probably plants, lived at an epoch immensely remote, long anterior to the primordial zone of the Silurian system, but I 1866

I 1859 1860 1861

We now know that at least one animal did then exist; but I 1869 1872

→ OMIT 1866 1869 1872

as far as we can see, 1859 1860 1861

→ extended for an enormous period, 1866 1869 1872

for an enormous period extended, 1859 1860 1861

→ commencement of the Silurian epoch; 1866

Silurian epoch; 1859 1860 1861

commencement of the Cambrian system; 1869 1872

→ only as remnants 1866 1869 1872

all be 1859 1860 1861

→ seem to me simply to follow on 1859 1860 1861 1866 1869

agree admirably with 1872

→ natural 1859 1860 1861 1866 1869

variation and natural 1872

He who rejects

this

these

view

views

the

nature

imperfection

of the geological record, will rightly reject

the

whole theory. For he may ask in vain where are the numberless transitional links which must formerly have connected the closely allied or representative species, found in the

several

successive

stages of the same great

formation.

formation?

He may disbelieve in the

immense

enormous

intervals of time which

must have

have

elapsed between our consecutive formations; he may overlook how important a part migration

has

must have

played, when the formations of any one great

region,

region

~~alone,~~

alone,

those

that

of Europe, are considered; he may urge the apparent, but often falsely apparent, sudden coming in of whole groups of species. He may ask where are the remains of those infinitely numerous organisms which must have existed long before the →first bed of the Silurian system was

deposited:

deposited?

→We now know that animals, and probably plants, lived at an epoch immensely remote, long anterior to the primordial zone of the Silurian system, but I can answer

this latter

this last

the above

question only

hypothetically,

....

saying

supposing

that →OMIT where our oceans now extend they have →extended for an enormous period, and where our oscillating continents now stand they have stood

ever

....

since the →commencement of the Silurian epoch; but

that

that,

long before that

epoch,

period,

the world

may have

....

presented a

wholly

widely

different aspect; and that the older continents, formed of formations older than any known to us,

may

exist

now →only as remnants in a metamorphosed condition, or

may

....

lie

buried

still buried

wholly buried

under the ocean.

Passing from these difficulties,

all

....

the other great leading facts in palæontology →seem to me simply to follow on the theory of descent with modification through →natural selection. We can thus understand how it is that new species come in slowly and successively; how species of different classes do not

necessarily,

necessarily

change together, or at the same rate, or in the same degree;