north of England, growing at considerable elevations. It
was first found at Ingleborough, in Yorkshire, and lias been
since met with on the limestone ranges of Westmoreland
and Lancashire. In cultivation it is usually a free-growing
plant, more lax than in the wild state, and one of the most
elegant of the larger kinds.
L astrea s p in u l o sa , Presl. — The Narrow Prickly-
toothed, or Crested Pern.
This is a rather erect-growing kind, with a stout stem or
root-stock, which becomes branched, so that several crowns
are generally found together forming one mass. The crowns
may readily be separated, and in this way the species maybe
increased with much facility. The fronds grow from one
0 three feet high, and are bipinnate, the pinnæ having an
obliquely tapering form from the inferior pinnules being
larger than the superior ones : this is most obvious at the
base of the fronds, where the pinnæ are broader than they
are towards the apex. The pinnules are of an oblong form,
somewhat narrowing upwards, the margins deeply incised,
the lobes being serrated, and the teeth somewhat spinulose;
—this description, it should be remembered, applies to the
lowest pinnules on the lowest pinnæ ; those towards the
apex of each pinna, as well as the basal ones of the pinnæ
nearer the apex of the frond, become gradually less and less
compound, so that, although the margins are still furnished
with spinulose teeth, they gradually lose the deep lobes
which are found on the lowest pinnæ. In all the more compound
Eerns there is a similar difference of form according
to the position of the pinnules, and in all such cases it is
usual to describe only those which are the most complete,
namely, such as are situated at the base of a few of the
lowermost pinnæ. The stipes of Lastrea spinulosa is rather
sparingly furnished with semitransparent scales of a broad
or bluntly ovate form, in which particular it agrees with cristata
and uliginosa, but differs from dilatata an i foenisecii.
The venation of all these allied species is so very similar,
that it is unnecessary to repeat the description in detail. In
the less divided pinnules there is a midrib, less tortuous
than in cristata, which gives off branched venules, the lower
anterior veinlets proceeding from which bear the sori, about
midway between the rib and the margin ; the clusters of
spore-cases thus forming an even double row on each piimule.
When the pinnule is more divided, the same arrangement
of the sori occurs on the lobes, the branches of the lateral
veins or venules being then more numerous. The sori are
covered by kidney-shaped indusia, having the margin entire.