CHAPTER X. ON THE IMPERFECTION OF THE GEOLOGICAL RECORD.
6. ON THE SUDDEN APPEARANCE OF GROUPS OF ALLIED SPECIES IN THE LOWEST KNOWN FOSSILIFEROUS STRATA. (continued)
The several difficulties here discussed, namely, that, though we find in
our geological formations many links between the species which now exist
and which formerly existed, we do not find infinitely numerous fine
transitional forms closely joining them all together. The sudden manner in
which several groups of species first appear in our European formations,
the almost entire absence, as at present known, of formations rich in
fossils beneath the Cambrian strata, are all undoubtedly of the most
serious nature. We see this in the fact that the most eminent
palaeontologists, namely, Cuvier, Agassiz, Barrande, Pictet, Falconer, E.
Forbes, etc., and all our greatest geologists, as Lyell, Murchison,
Sedgwick, etc., have unanimously, often vehemently, maintained the
immutability of species. But Sir Charles Lyell now gives the support of
his high authority to the opposite side, and most geologists and
palaeontologists are much shaken in their former belief. Those who believe
that the geological record is in any degree perfect, will undoubtedly at
once reject my theory. For my part, following out Lyell's metaphor, I look
at the geological record as a history of the world imperfectly kept and
written in a changing dialect. Of this history we possess the last volume
alone, relating only to two or three countries. Of this volume, only here
and there a short chapter has been preserved, and of each page, only here
and there a few lines. Each word of the slowly-changing language, more or
less different in the successive chapters, may represent the forms of life,
which are entombed in our consecutive formations, and which falsely appear
to have been abruptly introduced. On this view the difficulties above
discussed are greatly diminished or even disappear.
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