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of the earth as it at present exists； it is； indeed； a most astounding
thing that the proportion of extinct ordinal types should be so
exceedingly small。
But now； there is another point of view in which we must look at this
past creation。 Suppose that we were to sink a vertical pit through the
floor beneath us； and that I could succeed in making a section right
through in the direction of New Zealand； I should find in each of the
different beds through which I passed the remains of animals which I
should find in that stratum and not in the others。 First； I should
come upon beds of gravel or drift containing the bones of large
animals； such as the elephant； rhinoceros； and cave tiger。 Rather
curious things to fall across in Piccadilly！ If I should dig lower
still； I should come upon a bed of what we call the London clay； and in
this； as you will see in our galleries upstairs； are found remains of
strange cattle； remains of turtles； palms； and large tropical fruits；
with shell…fish such as you see the like of now only in tropical
regions。 If I went below that； I should come upon the chalk； and there
I should find something altogether different； the remains of
ichthyosauri and pterodactyles； and ammonites； and so forth。
I do not know what Mr。 Godwin Austin would say comes next； but probably
rocks containing more ammonites； and more ichthyosauri and plesiosauri；
with a vast number of other things； and under that I should meet with
yet older rocks； containing numbers of strange shells and fishes； and
in thus passing from the surface to the lowest depths of the earth's
crust； the forms of animal life and vegetable life which I should meet
with in the successive beds would； looking at them broadly； be the more
different the further that I went down。 Or； in other words； inasmuch
as we started with the clear principle； that in a series of
naturally…disposed mud beds the lowest are the oldest； we should come
to this result； that the further we go back in time the more difference
exists between the animal and vegetable life of an epoch and that which
now exists。 That was the conclusion to which I wished to bring you at
the end of this Lecture。
End