WN FOSSIL FLORAS OF SCOTLAND.

PART II.

In the noble flora of the Coal Measures much still remains to be done in
Scotland. Our Lower Carboniferous rocks are of immense development; the
Limestones of Burdiehouse, with their numerous terrestrial plants, occur
many hundred feet beneath our Mountain Limestones; and our list of
vegetable species peculiar to these lower deposits is still very
incomplete. Even in those higher Carboniferous rocks with which the many
coal workings of the country have rendered us comparatively familiar,
there appears to be still a good deal of the new and the unknown to
repay the labor of future exploration. It was only last year that Mr.
Gourlay[53] of this city (Glasgow) added to our fossil flora a new
Volkmannia from the coal field of Carluke; and I detected very recently
in a neighboring locality (the Airdrie coal field), though in but an
indifferent state of keeping, what seems to be a new and very peculiar
fern. It presents at first sight more the appearance of a Cycadaceous
frond than any other vegetable organism of the Carboniferous age which I
have yet seen. From a mid stem there proceed at right angles, and in
alternate order, a series of sessile, lanceolate, acute leaflets, nearly
two inches in length by about an eighth part of an inch in breadth, and
about three lines apart. Each is furnished with a slender midrib; and,
what seems a singular, though not entirely unique, feature in a fern,
their edges are densely hirsute, and bristle with thick, short hair,
nearly as stiff as prickles. The venation is not distinctly preserved;
but enough remains to show that it must have been peculiar,--apparently
radiating outwards from a series of centres ranged along the midrib.
Nay, the apparent hairs seem to be but prolongations of the nerves
carried beyond the edges of the leaflets. There is a Stigmaria, too, on
the table, very ornate in its sculpture, of which I have now found three
specimens in a quarry of the Lower Coal Measures near Portobello, that
has still to be figured and described. In this richly ornamented
Stigmaria the characteristic areolae present the ordinary aspect. Each,
however, forms the centre of a sculptured star, consisting of from
eighteen to twenty rays, or rather the centre of a sculptured flower of
the composite order, resembling a meadow daisy or sea-aster. The minute
petals,--if we are to accept the latter comparison,--are of an
irregularly lenticular form, general