observation and experiment upon the existing forms of life, the
conclusion will inevitably present itself, that the Paleozoic,
Mesozoic, and Cainozoic faunae and florae, taken together, bear
somewhat the same proportion to the whole series of living beings which
have occupied this globe, as the existing fauna and flora do to them.

Such are the results of paleontology as they appear, and have for some
years appeared, to the mind of an inquirer who regards that study
simply as one of the applications of the great biological sciences, and
who desires to see it placed upon the same sound basis as other
branches of physical inquiry. If the arguments which have been brought
forward are valid, probably no one, in view of the present state of
opinion, will be inclined to think the time wasted which has been spent
upon their elaboration.