species of conifers;
and its great forests, of whose existence we have direct evidence in the
very abundant lignites of the system, must have possessed a richness and
variety which our ancient fir woods of the historic or human period
could not have possessed. With the Conifers and the Cycadeae there were
many ferns associated,--so many, that they still composed nearly two
fifths of the entire flora; and associated with these, though in reduced
proportions, we find the fern allies. The reduction, however, of these
last is rather in species than in individuals. The Brora Coal, one of
the most considerable Oolitic seams in Europe, seems to have been formed
almost exclusively of an equisetum,--_E. columnare_. In this flora the
more equivocal productions of the Coal Measures are represented by what
seems to be the last of the Calamites; but it contains no
Lepidodendra,--no Ulodendra,--no Sigillaria,--no Favularia,--no Knorria
or Halonia. Those monsters of the vegetable world that united to the
forms of its humbler productions the bulk of trees, had, with the
solitary exception of the Calamites, passed into extinction; and ere the
close of the system they too had disappeared. The forms borne by most of
the Oolitic plants were comparatively familiar forms. With the Acrogens
and Gymnogens we find the first indication of the Liliaceae, or lily-like
plants,--of plants, too, allied to the Pandanaceae or screw pines, the
fruits of which are sometimes preserved in a wonderfully perfect state
of keeping in the Inferior Oolite, together with Carpolithes,--palm-like
fruits, very ornately sculptured,--and the remains of at least one other
monocotyledon, that bears the somewhat general name of an Endogenite.
With these there occur a few disputed leaves, which I must persist in
regarding as dicotyledonous. But they formed, whatever their true
character, a very inconspicuous feature in the Oolitic flora; and not
until the overlying Cretaceous System is ushered in do we find leaves in
any considerable quantity decidedly of this high family; nor until we
enter into the earlier Tertiaries do we succeed in detecting a true
dicotyledonous tree. On such an amount of observation is this order of
succession determined,--though the evidence is, of course, mainly
negative,--that when, some eight or ten years ago, Dr. John Wilson, the
learned Free Church missionary to the Parsees of India, submitted to me
specimens of fossil woods which he had picked