Chap. TX. 
GEOLOGICAL KECOED. 
311 
in which whole groups of species appear in our Euro¬ 
pean formations; the almost entire absence, as at pre¬ 
sent known, of fossiliferous formations beneath the Si¬ 
lurian strata, are all undoubtedly of the gravest nature. 
We see this in the plainest manner by the fact that 
all the most eminent palaeontologists, namely Cuvier, 
Agassiz, Barrande, Falconer, E. Forbes, &c.’, and all 
our greatest geologists, as Lyell, Murchison, Sedgwick, 
&c., have unanimously, often vehemently, maintained 
the immutability of species. But I have reason to be¬ 
lieve that one great authority. Sir Charles Lyell, from 
further reflexion entertains grave doubts on this subject. 
I feel how rash it is to differ from these authorities, to 
whom, with others, we owe all our knowledge. Those 
who think the natural geological record in any degree 
perfect, and who do not attach much weight to the facts 
and arguments of other kinds given in this volume, will 
undoubtedly at once reject my theory. For my part, 
following out Lyell’s metaphor, I look at the natural 
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, in which the history is sup¬ 
posed to be written, being more or less different in the 
interrupted succession of chapters, may represent the 
apparently abruptly changed forms of life, entombed in 
our consecutive, but widely separated, formations. On 
this view, the difficulties above discussed are greatly 
diminished, or even disappear. 
