See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1861
1866
1869
1872

percentage system of 1859 1860 1861 1866 1869
proportion between the 1872

CHAPTER
XI.
X.
ON THE GEOLOGICAL SUCCESSION OF
ORCANIC
ORGANIC
BEINGS.
On the slow and successive appearance of new species— On their different rates of change— Species once lost do not reappear— Groups of species follow the same general rules in their appearance and disappearance as do single species— On
extinction—
Extinction—
On simultaneous changes in the forms of life throughout the world— On the affinities of extinct species to each other and to living species— On the state of development of ancient forms— On the succession of the same types within the same areas— Summary of preceding and present
chapter.
chapters.
LET us now see whether the several facts and
laws
rules
relating to the geological succession of organic
beings
beings,
better
better
accord
best with
with
the common view of the immutability of species, or with that of their slow and gradual modification, through
variation
descent
and natural selection.
New species have appeared very slowly, one after another, both on the land and in the waters. Lyell has shown that it is hardly possible to resist the evidence on this head in the case of the several tertiary stages; and every year tends to fill up the blanks between
the stages,
them,
and to make the percentage system of lost and
existing
new
forms more gradual. In some of the most recent beds, though undoubtedly of high antiquity if measured by years, only one or two species are
extinct,
lost forms,
and only one or two are
new,
new
forms,
forms,
having
appeared
appeared there
here appeared
for the first time, either locally, or, as far as we know, on the face of the earth. If we may trust the observations of Philippi in Sicily, the successive changes in the marine inhabitants of that island have been many and most gradual. The secondary formations are more broken; but, as Bronn has remarked, neither the appearance