nd, wherever
sufficiently numerous series of the remains of any given group, which
has endured for a long space of time, are carefully examined, their
morphological relations are never in discordance with the requirements
of the doctrine of evolution, and often afford convincing evidence of
it. At the same time, it has been shown that certain forms persist
with very little change, from the oldest to the newest fossiliferous
formations; and thus show that progressive development is a
contingent, and not a necessary result, of the nature of living
matter.

[Sidenote: Geology.]

Geology is, as it were, the biology of our planet as a whole. In so
far as it comprises the surface configuration and the inner structure
of the earth, it answers to morphology; in so far as it studies
changes of condition and their causes, it corresponds with physiology;
in so far as it deals with the causes which have effected the progress
of the earth from its earliest to its present state, it forms part of
the general doctrine of evolution. An interesting contrast between the
geology of the present day and that of half a century ago, is
presented by the complete emancipation of the modern geologist from
the controlling and perverting influence of theology, all-powerful at
the earlier date. As the geologist of my young days wrote, he had one
eye upon fact, and the other on Genesis; at present, he wisely keeps
both eyes on fact, and ignores the pentateuchal mythology altogether.
The publication of the 'Principles of Geology' brought upon its
illustrious author a period of social ostracism; the instruction given
to our children is based upon those principles. Whewell had the
courage to attack Lyell's fundamental assumption (which surely is a
dictate of common sense) that we ought to exhaust known causes before
seeking for the explanation of geological phenomena in causes of which
we have no experience. But geology has advanced to its present state
by working from Lyell's[J] axiom; and, to this day, the record of the
stratified rocks affords no proof that the intensity or the rapidity
of the causes of change has ever varied, between wider limits, than
those between which the operations of nature have taken place in the
youngest geological epochs.

An incalculable benefit has accrued to geological science from the
accurate and detailed surveys, which have now been executed by skilled
geologists employed by the Governments of all parts of the civ