And future geologists would have found--they
may find yet, if, which God forbid, England should become barbarous
and the trees be thrown out of cultivation--instead of fossil
Lepidodendra and Sigillariae, Calamites and ferns, fossil ashes and
oaks, alders and poplars, bulrushes and reeds. Almost the only
fossil fern would have been that tall and beautiful Lastraea
Thelypteris, once so abundant, now all but destroyed by drainage and
the plough.
We need not, therefore, fancy any extraordinary state of things on
this planet while our English coal was being formed. The climate of
the northern hemisphere--Britain, at least, and Nova Scotia--was
warmer than now, to judge from the abundance of ferns; and especially
of tree-ferns; but not so warm, to judge from the presence of
conifers (trees of the pine tribe), as the Tropics. Moreover, there
must have been, it seems to me, a great scarcity of animal-life.
Insects are found, beautifully preserved; a few reptiles, too, and
land-shells; but very few. And where are the traces of such a
swarming life as would be entombed were a tropic forest now sunk;
which is found entombed in many parts of our English fens? The only
explanation which I can offer is this--that the club-mosses, tree-
ferns, pines, and other low-ranked vegetation of the coal afforded
little or no food for animals, as the same families of plants do to
this day; and if creatures can get nothing to eat, they certainly
cannot multiply and replenish the earth.
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