And here is a cast of the pterodactyle and bones of
the ichthyosaurus and the plesiosaurus, just as fresh as if it had been
recently dug up in a churchyard. Thus, in the reptile class, there are
no less than half of the orders which are absolutely extinct. If we
turn to the 'Amphibia', there was one extinct order, the
Labyrinthodonts, typified by the large salamander-like beast shown in
this diagram.
No order of fishes is known to be extinct. Every fish that we find in
the strata--to which I have been referring--can be identified and
placed in one of the orders which exist at the present day. There is
not known to be a single ordinal form of insect extinct. There are
only two orders extinct among the 'Crustacea'. There is not known to
be an extinct order of these creatures, the parasitic and other worms;
but there are two, not to say three, absolutely extinct orders of this
class, the 'Echinodermata'; out of all the orders of the 'Coelenterata'
and 'Protozoa' only one, the Rugose Corals.
So that, you see, out of somewhere about 120 orders of animals, taking
them altogether, you will not, at the outside estimate, find above ten
or a dozen extinct. Summing up all the orders of animals which have
left remains behind them, you will not find above ten or a dozen which
cannot be arranged with those of the present day; that is to say, that
the difference does not amount to much more than ten per cent.
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