Origin of Species Variorum

→ records of these vast primordial periods, 1859 1860 1861

richly fossiliferous records of these vast primordial periods, 1866

rich fossiliferous deposits belonging to these assumed earliest periods, 1869

rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system, 1872

→ of the most 1859 1860 1861

OMIT 1866 1869 1872

→ are 1859 1860 1861

were until recently 1866 1869 1872

→ M. Barrande has lately 1859 1860 1861

M. Barrande not long ago 1866

Not long ago M. Barrande 1869

Not very long ago M. Barrande 1872

→ to the Silurian system, 1859 1860 1861 1866

OMIT 1869 1872

→ species. 1859 1860 1861 1866

species beneath the old Silurian system. 1869

species, beneath the then known Silurian system; and now, still lower down in the Lower Cambrian formation, Mr. Hicks has found in South Wales beds rich in trilobites, and containing various molluscs and annelids. 1872

→ life have 1859 1860 1861

several forms have 1866

several forms have also 1869

→ in the Longmynd beds, 1860 1861 1866

in the Longmynd beds 1859

OMIT 1869

→ zone. 1859 1860 1861 1866

zone in the Longmynd group, now divided into two stages, and constituting the Lower Cambrian system. 1869

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

Still more recently, the remarkable discovery has been made by Torell of the remains of monocoty-ledonous plants in a Swedish formation, corresponding with the Longmynd group; so that terrestrial or freshwater plants existed several great stages lower down in the series than has hitherto been supposed.

→ the difficulty of understanding the absence of vast piles of fossiliferous strata, which on my theory no doubt were somewhere accumulated before the Silurian epoch, is very great. 1859 1860 1861

now within the last year the great discovery of the Eozoon in the Laurentian formation of Canada has been made; and after reading Dr. Carpenter's description of this remarkable fossil, it is impossible to feel any doubt regarding its organic nature. 1866

→ If these 1859 1860 1861

If the 1866

It does not seem probable that the 1869 1872

→ obliterated 1859 1860 1861

if their fossils had been wholly obliterated 1866

that their fossils have been wholly obliterated 1869 1872

→ we ought to find 1859 1860 1861

we ought to have found 1866

for if this had been the case we should have found 1869 1872

→ ought to be very generally 1859 1860 1861

ought to have existed almost always 1866

would always have existed 1869 1872

→ always suffered the extremity of 1860 1861 1866

suffered the extremity of 1859

invariably suffered extreme 1869

suffered extreme 1872

To the question why we do not find →records of these vast primordial periods, I can give no satisfactory answer. Several →of the most eminent geologists, with Sir R. Murchison at their head, →are convinced that we

beheld

see

in the organic remains of the lowest Silurian stratum the

first dawn

life.

~~this~~

~~planet.~~

Other highly competent judges, as Lyell and

~~the late~~

the late

E. Forbes ,

disputed

have disputed

dispute

this conclusion. We should not forget that only a small portion of the world is known with accuracy. →M. Barrande has lately added another and lower

stage,

stage

→to the Silurian system, abounding with new and peculiar →species.

Remnants

Traces

of →life have been detected →in the Longmynd beds, beneath

Barrande's

Barrandes

so-called primordial →zone. ↑ The presence

also of

phosphatic nodules and bituminous matter in some of the lowest azoic rocks, probably indicates the former existence of life at these periods. But →the difficulty of understanding the absence of vast piles of fossiliferous strata, which on my theory no doubt were somewhere accumulated before the Silurian epoch, is very great. →If these most ancient beds

have

had

been

generally

quite

wholly

worn away by denudation, or →obliterated by metamorphic action, →we ought to find only small remnants of the formations next succeeding them in age, and these →ought to be very generally in a

partially metamorphosed

metamorphosed

condition. But the descriptions which we

~~now~~

now

possess of the Silurian deposits over immense territories in Russia and in North America, do not support the view, that the older a formation is, the more

invariably it

has →always suffered the extremity of denudation and metamorphism.

The case at present must remain inexplicable; and may be truly urged as a valid argument against the views here entertained. To show that it may hereafter receive some explanation, I will give the following hypothesis. From the nature of the organic

remains,

remains

which