Origin of Species Variorum

→ level. 1859 1860 1861 1866

level, as well as the subsequent subaerial degradation. 1869 1872

→ 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

and peculiar marine faunas will probably be preserved to a distant age. A little reflection will explain

why,

why

along the rising coast of the western side of South America, no extensive formations with recent or tertiary remains can anywhere be found, though the supply of sediment must for ages have been great, from the enormous degradation of the coast-rocks and from muddy streams entering the sea. The explanation, no doubt, is, that the littoral and sub-littoral deposits are continually worn away, as soon as they are brought up by the slow and gradual rising of the land within the grinding action of the coast-waves.

We may, I think,

~~safely~~

safely

conclude that sediment must be accumulated in extremely thick, solid, or extensive masses, in order to withstand the incessant action of the waves, when first upraised and during

successive

subsequent

oscillations of →level. Such thick and extensive accumulations of sediment may be formed in two ways;

either

either,

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,