in dealing
with the ferns, founds his generic distinctions, I could only determine
that it was either a Cyclopterus or Neuropterus. My collection was
visited, however, by the late lamented Edward Forbes, only a few weeks
before his death; and he at once recognized in my Berwickshire fern, so
unequivocally an organism of the Upper Old Red, the _Cyclopterus
Hibernicus_ of those largely developed beds of yellow sandstone which
form so marked a feature in the geology of the south of Ireland, and
whose true place, whether as Upper Old Red or Lower Carboniferous, has
been the subject of so much controversy. I had been previously
introduced by Professor Forbes, in the Museum of Economic Geology in
Jermyn Street, London, to an interesting collection of plants from these
yellow beds, and had an opportunity afforded me of examining the only
ichthyic organism hitherto found associated with them; and was struck,
though I could not identify its species, with its peculiarly Old Red
aspect; but the evidence of the Cyclopterus is of course more conclusive
than that of the fish; and we may, I think, legitimately conclude, that
in Ireland, as in our own country, it was a contemporary of the great
Pterichthys (_P. major_),--the hugest, and at least one of the last, of
his race,--and gave its rich green to the hill sides of what is still
the Emerald Island during the latter ages of the Old Red Sandstone, and
ere the Carboniferous period had yet begun. The _Cyclopterus
Hibernicus_, as shown both by the Prestonhaugh specimen and those of
Ireland, was a bipinnate fern of very considerable size,--probably a
tree fern. Its pinnae, opposite in the lower part of the frond, are
alternate in the upper; while its leaflets, which are of a
sub-rhomboidal form, and so closely ranged as to impinge on each other,
are at least generally alternate in their arrangement throughout. Among
living plants it seems most nearly represented by a South American
species,--_Didymocloena pulcherrima_,--one of the smaller tree ferns.
The leaves of this graceful species are bipinnate, like those of the
fossil; and the pinnae (thickly set with simple, alternately arranged
leaflets) are opposite in the lower part of the frond, and alternate in
the upper. Widely as they are separated in time, the recent South
American Didymocloena and the Old Red Sandstone Cyclopterus, that
passed into extinction ere the times of the Coal, might be ranged
together, so far at least as appears