rupt cactus-like terminations of Ulodendron
repeated the evidence of Messrs. Lindley and Hutton's specimen regarding
the arrangement of the cone scars on opposite sides, and showed also
that these scars ascended to within little more than an inch of the top
of the plant.

As there are cases in which the _position_ of a fossil plant may add,
from its bearing on geologic history, a threefold interest to the fossil
itself, regarded simply as an organism, I may be permitted to refer to a
circumstance already recorded, that there was a well marked Bechera
detected about two years ago by Dr. Macbean of Edinburgh, an
accomplished naturalist and careful observer, in a thin argillaceous
stratum, interposed, in the Queen's Park, between a bed of columnar
basalt and a bed of trap-tuff, in the side of the eminence occupied atop
by the ruins of St. Anthony's Chapel. The stratified bed in which it
occurs seems, from its texture and color, to be composed mainly of
trappean materials, but deposited and arranged in water; and abounds in
carbonaceous markings, usually in so imperfect a state of keeping that,
though long known to some of the Edinburgh geologists, not a single
species, or even genus, were they able to determine. All that could be
said was, that they seemed fucoidal, and might of course belong to any
age. The Bechera, however, shows that the deposit is one of the Lower
Coal Measures. There was found associated with it a tooth of a
Carboniferous Holoptychius, whose evidence bore out the same conclusion;
and both fossils derive an importance from the light which they throw
on the age of the bed of tuff which underlies the stratum in which they
occur. At least this trap-rock must be as old as the fossiliferous layer
which rests upon it, or rather, as shown by its underlying position, a
little older: it must be a trap of the earlier Carboniferous period.
Further, it must have been, not injected among the strata, but poured
out over the surface,--in all probability covered at the time by water;
and there must have formed over it, ere another overflow of trap took
place, a thin sedimentary bed charged with fragments of the plants of
the period, and visited, when in the course of deposition, by some of
its fishes.

[Illustration: Fig. 129.

SPHENOPTERIS BIFIDA.

(_Burdiehouse._)]

Even among the vegetable organisms of our Coal Measures, already
partially described and figured, much remains to be accomplished in the
way of r