he seas of the world
have always been so freely open from south to north as they are at
present. Even at this day, if the Malay Archipelago were converted
into land, the tropical parts of the Indian Ocean would form a
large and perfectly enclosed basin, in which any great group of
marine animals might be multiplied; and here they would remain
confined, until some of the species became adapted to a cooler
climate, and were enabled to double the southern capes of Africa or
Australia, and thus reach other and distant seas.

From these considerations, from our ignorance of the geology of
other countries beyond the confines of Europe and the United
States; and from the revolution in our palaeontological knowledge
effected by the discoveries of the last dozen years, it seems to me
to be about as rash to dogmatize on the succession of organic
forms throughout the world, as it would be for a naturalist to
land for five minutes on some one barren point in Australia, and
then to discuss the number and range of its productions[53].

[53] _Origin of Species_, 282-5.

In view of all the foregoing facts and considerations, it appears to me
that the second difficulty on our list is completely answered. Indeed,
even on a moderate estimate of the imperfection of the geological
record, the wonder would have been if many cases had _not_ occurred
where groups of species present the fictitious appearance of having been
suddenly and simultaneously created in the particular formations where
their remains now happen to be observable.

Turning next to the third objection, there cannot be any question that
every here and there in the geological series animals occur of a much
higher grade zoologically than the theory of evolution would have
expected to find in the strata where they are found. At any rate,
speaking for myself, I should not have antecedently expected to meet
with such highly differentiated insects as butterflies and dragonflies
in the middle of the Secondaries: still less should I have expected to
encounter beetles, cockroaches, spiders, and May-flies in the upper and
middle Primaries--not to mention an insect and a scorpion even in the
lower. And I think the same remark applies to a whole sub-kingdom in the
case of Vertebrata. For although it is only the lowest class of the
sub-kingdom which, so far as we positively know, was represented in the