Origin of Species Variorum

→ judging from the researches of E. Forbes , we may conclude that 1859 1860 1861

judging from the rescarches of E. Forbes , we may conclude that 1866

OMIT 1869 1872

→ extremely few animals, 1859 1860

few animals, 1861 1866

so many and such varied forms of life, as the more shallow seas; 1869 1872

→ and the mass when upraised will give a most imperfect record of the forms of life which then existed; or, 1859 1860

but it will not be, as we at last know from the telegraphic soundings, barren of life; consequently the mass when up-raised will give a most imperfect record of the forms of life which existed during the period of deposition. Or, 1861

but it will not be, as we now know from telegraphic and other deep soundings, barren of life; consequently the mass when upraised will give a most imperfect record of the forms of life which existed during the period of deposition. Or, 1866

and the mass when upraised will give an imperfect record of the organisms which existed throughout the world during the period of its accumulation. Or, 1869

and the mass when upraised will give an imperfect record of the organisms which existed in the neighbourhood during the period of its accumulation. Or, 1872

→ thus a 1859 1860 1861 1866

varied forms, and thus a rich 1869 1872

→ rich 1859 1860

throughout the greater part of their thickness rich 1861

throughout the greater part of their thickness rich 1866 1869 1872

in profound depths of the sea, in which

case

case,

→judging from the researches of E. Forbes , we may conclude that the bottom will

not be

inhabited by →extremely few animals, →and the mass when upraised will give a most imperfect record of the forms of life which then existed; or, sediment may be

deposited

accumulated

to any thickness and extent over a shallow bottom, if it continue slowly to subside. In this latter case, as long as the rate of subsidence and

the supply

supply

of sediment nearly balance each other, the sea will remain shallow and favourable for

many

life,

and →thus a

rich fossiliferous

fossiliferous

formation,

formation

thick enough, when upraised, to resist

almost any

a large

any

amount of

denudation,

degradation,

may be formed.

I am convinced that

nearly all

all

our ancient formations, which are →rich

fossils ,

fossils,

fossils,

have thus been formed during subsidence. Since publishing my views on this subject in 1845, I have watched the progress of Geology, and have been surprised to note how author after author, in treating of this or that great formation, has come to the conclusion that it was accumulated during subsidence. I may add, that the only ancient tertiary formation on the west coast of South America, which has been bulky enough to resist such degradation as it has as yet suffered, but which will hardly last to a distant geological age, was

~~certainly~~

certainly

deposited during a downward oscillation of level, and thus gained considerable thickness.

All geological facts tell us plainly that each area has undergone numerous slow oscillations of level, and apparently these oscillations have affected wide spaces.

Consequently,

Consequently

formations rich in fossils and sufficiently thick and extensive to resist subsequent degradation,

will

may

have been formed over wide spaces during periods of subsidence, but only where the supply of sediment was sufficient to keep the sea shallow and to embed and