of its most successful votaries. So constantly has this
species been confounded with H . tunbridgense, that it is
perhaps impossible to give any certain reference to the
works of Ray, or of any later author : it appears also to
have been wholly unobserved on the Continent. Probably
the “ Adiantum petraeum perpusillum, foliis bifidis, trifidis-
que" of R. Syn. 123. may relate to this species, and perhaps
also the u Darea tunbridgensis minor" of Pet. Mus. 762.(?)
None of the figures in Bolton’s Filices represents this
plant. Tab. 2. f. 7., though the specimen said to have been
brought from Dolbadarn Castle (where H . Wilsoni only
is now to be seen), is a figure of U . tunbridgense; so also
is tab. 31., as is evident in the truly bipinnatifid division
of the frond in both instances. Tab. 30. of the same work
is a sufficiently intelligible figure of Trichomanes brevisetum
of modern authors, in a young state (essentially distinguished
in every stage by the absence of serratures on the
ultimate divisions of the frond).
I I . Wilsoni is more rigid than I I . tunbridgense, and more
coarsely reticulated. Frond oblong, on a shorter stalk, the
pinnae obliquely attached, and often much recurved; the
segments not so evidently toothed at the apex, and their
nei’ve is continued to the extremity. Involucre with very
convex valves; so as to appear compressed in a contrary
direction to the convexity; its stalk much bent upwards.
Colour of the plant dark green. It curls much in drying.
When growing in favourable situations on the perpendicular
faces of moist shaded rocks, the fronds are nearly pendulous
; as is the case also with H . tunbridgense. Fruit ripe
in October.
H . tunbridgense has its texture more closely reticulated;
the involucre is sessile; the segments of the pinnae sharply
toothed at the extremity, and their nerve evidently discontinued.
Colour of the frond of a pale glassy green. The
pinnae divided into more numerous segments (frequently
ten), which point in two directions on each side of the midrib
; those on the outside nearly at right angles with the
rachis.—W. W ilsojs.