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geography of fossils. 
as they once were when their dark proto¬ 
types flourished. 
^ If we follo w the course of the mighty Mis¬ 
sissippi, we shall sail down through foliage 
of ever varying character, from the slender 
leaf of the birch, to the noble crown of the 
palm ; but we might mine into subterranean 
beds parallel to the whole of its long stream, 
and And no variance whatever in the fossil 
forms imprinted on their strata. 
Th e fossil plants from Cape Breto n coal field, 
are undistinguishable from those of our own 
collieries, and what is still more remarkable, 
identical also with those of Pennsylvania, 
Maryland, and Ohio; whilst the existing 
flora of all these countries differs as widely 
as their several climates. Even here, how¬ 
ever, we find that existing analogies do not 
quite fail us, for whilst this remarkable uni¬ 
formity extends unbroken over so vast an 
area, yet the coal fields of the more south¬ 
ern region of Indiana do exhibit some va¬ 
riations from the northern type, and those 
of New Holland present us with many forms 
altogether unknown in Euroj)e. 
The fossil remains usually occur in layers 
