ly be dissolved by the percolation of rain-water."

{112} The position of the following is not clear:--"Think of
immense differences in nature of European deposits,--without
interposing new causes,--think of time required by present slow
changes, to cause, on very same area, such diverse deposits,
iron-sand, chalk, sand, coral, clay!"

{113} The paragraph which ends here is difficult to interpret. In
spite of obscurity it is easy to recognize the general resemblance
to the discussion on the importance of subsidence given in the
_Origin_, Ed. i. pp. 290 et seq., vi. pp. 422 et seq.

I believe safely inferred <that> groups of marine <?> fossils only
preserved for future ages where sediment goes on long <and>
continuous<ly> and with rapid but not too rapid deposition in <an> area
of subsidence. In how few places in any one region like Europe will <?>
these contingencies be going on? Hence <?> in past ages mere [gaps]
pages preserved{114}. Lyell's doctrine carried to extreme,--we shall
understand difficulty if it be asked:--what chance of series of
gradation between cattle by <illegible> at age <illegible> as far back
as Miocene{115}? We know then cattle existed. Compare number of
living,--immense duration of each period,--fewness of fossils.

{114} See Note 3, p. 27.

{115} Compare _Origin_, Ed. i. p. 298, vi. p. 437. "We shall,
perhaps, best perceive the improbability of our being enabled to
connect species by numerous, fine, intermediate, fossil links, by
asking ourselves whether, for instance, geologists at some future
period will be able to prove that our different breeds of cattle,
sheep, horses, and dogs have descended from a single stock or from
several aboriginal stocks."

This only refers to consecutiveness of history of organisms of each
formation.

The foregoing argument will show firstly, that formations are distinct
merely from want of fossils <of intermediate beds>, and secondly, that
each formation is full of gaps, has been advanced to account for
_fewness_ of _preserved_ organisms compared to what have lived on the
world. The very same argument explains why in older formations the
organisms appear to come on and disappear suddenly,--but in [later]
tertiary not quite suddenly{116}, in later tertiary gradually,--becoming
rare and disappearing,--some have disappeared within man's time. It is
obvious that our theory req