286                                                       SILURIA.                                          [Chap. XII.
 

CHAPTEE XII.
CARBONIFEROUS ROCKS.

great primeval flora the source of the old coal deposits.----GENERAL VIEW OF THESE

DEPOSITS AND THEIR ORGANIC REMAINS IN THE BRITISH ISLES.

Ascending in the scale of deposits, we have now reached another grand
accumulation of strata, which is not only replete with many types of
animal life pecrUiar to it and unknown in antecedent periods, but is spe¬
ciaUy characterized by the earliest very abundant remains of a terrestrial
vegetation. The reader wUl remember that feeble traces only of Land
Plants have been discovered in the uppermost SUurian rocks. In the
Devonian rocks, also, such remains, as before stated, are comparatively
rare *, and only abound when we have passed upwards and are surrounded
by the spoUs of the oldest extensive forests with which we are acquainted.
Now, as these primeval Plants were the substances out of which the
great mass of coal has been formed, so we meet for the first time, in
mounting up from the basement-rocks, with a profusion of the impressions
and casts of Plants in stone. Some idea of the characters of the luxuriant
vegetation which must in this age have overspread very wide areas of
land, from polar to nearly equatorial latitudes, may be formed by inspect¬
ing the annexed woodcut, in which an ideal representation is given of a
 

Ideal View of the Vegetation of the Carboniferous Era.

portion of the earth's surface as clothed with Plants the fragments of
which bespeak a rich flora of Vascular Cryptogams, whose fossilized stems
and leaves occur frequently in the shale and sandstone of the coal-fields,
and, indeed, constitute the coal itself. In the standard work of Bronn,
von Meyer, and Goppert, which gives the most complete general tabular

* Though rare in Britain, Land Plants are comparatively numerous in the Devonian rocks of Gasndi
and NevF Brunswick, as will be shown hereafter.