restrial flora at periods antecedent to the coal. In the
carboniferous epoch, about 500 species of fossil plants are enumerated
by Adolphe Brongniart, which we may safely regard as a mere fragment of
an ancient flora; since, in Europe alone, there are now no less than
11,000 living species. I have already hinted that the plants which
produced coal were not drifted from a distance, but that nearly all of
them grew on the spots where they became fossil. They appear to have
belonged, as before explained (p. 115), to a peculiar class of
_stations_,--to low level and swampy regions, in the deltas of large
rivers, slightly elevated above the level of the sea. From the study,
therefore, of such a vegetation, we can derive but little insight into
the nature of the contemporaneous upland flora, still less of the plants
of the mountainous or Alpine country; and if so, we are enabled to
account for the apparent monotony of the vegetation, although its
uniform character was doubtless in part owing to a greater uniformity of
climate then prevailing throughout the globe. Some of the commonest
trees of this period, such as the sigillariae, which united the structure
of ferns and of cycadeae, departed very widely from all known living
types. The coniferae and ferns, on the contrary, were very closely allied
to living genera. It is remarkable that none of the exogens of Lindley
(dicotyledonous angiosperms of Brongniart), which comprise four-fifths
of the living flora of the globe, and include all the forest trees of
Europe except the fir-tribe, have yet been discovered in the coal
measures, and a very small number--fifteen species only--of
monocotyledons. If several of these last are true plants, an opinion to
which Messrs. Lindley, Unger, Corda, and other botanists of note
incline, the question whether any of the most highly organized plants
are to be met with in ancient strata is at once answered in the
affirmative. But the determination of these palms being doubtful, we
have as yet in the coal no positive proofs either of the existence of
the most perfect, or of the most simple forms of flowering or flowerless
vegetation. We have no fungi, lichens, hepatici or mosses: yet this
latter class may have been as fully represented then as now.

In the flora of the secondary eras, all botanists agree that palms
existed, although in Europe plants of the family of zamia and cycas
together with coniferae predominated, and must have given a pecul