[361]

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Jan. 30. 1861. Woodward showed me lists, showing how very larger proportions of Kinds & numbers dead shells are to living in Dredge. Young Woodward in Mr M'Andrew thinks shells take immense time to decay at bottom of sea. I saw some of very little spec. gravity & drilled by Cliœna & very tender. Shells in this state are often Kept together by serpulæ &c. It does not seem that dredge brings up shells in last steps of decay. But such shells, as just described must ultimately decay. Perhaps such shells dropped in Dredge & joisted with other shells would generally get knocked to pieces & fragments washed away.

Consider well my statement at p. 319 of 3d Edit. of Origin abt shells at bottom or top above of thick deposits. Such

361v]

G.R p. 319. & Decay of shell abt upper & lower part of formation

during Elevation might possess a collection of fossils: but formed during comparatively short period & forming most imperfect records so during rapid sediment the basal beds alone would preserve shallow sea organisms

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