2724
ASPIDIUM rigidum.
Rigid Shield-fern,
CR YPTOGAMIA Filices.
Gen. Char, Clusters of fructification roundish, scattered.
Involucre orbicular, fixed by the centre,
or orbiculari-reniform, and fixed at the sinus.
Spec. Char. Fronds lanceolate, bipinnate. Pinnules
subcordato-oblong, obtuse, pinnatifido-
serrate ; the segments sub-bidentate ; the teeth
mucronulate. Stipes and rachis chaffy. Fructifications
in the upper half of the frond.
Syn. Aspidium rigidum. Swartz, Syn. Fil. 53.
Schkuhr, Fil. 40. t. 38. Willd. Sp. PL v. 5.
265. Hook. Brit. FI. ed. 2. 442.
A. spinulosum y. Hook. Brit. Fl. ed. 1. 444.
Polystichum rigidum. Decand. Dubis, Bot. Gall,
v. 1. 538.
Polypodium rigidum. Hoffm. FI. Germ. v. 2. 6.
S t i p e s 2 to 4 inches in length, clothed as is the rachis
throughout with linear-subulate chaffy scales. Frond from
6 to 8 or 10 inches or a foot high, lanceolate, bipinnate,
of a rather rigid habit, and of a dark green colour. The
pinnae closely arranged, cordato-lanceolate, with close-set
oblong or oblongo-cordate pinnules, from | to f of an inch
long: these are obtuse, glabrous on both sides, pinnatifid,
with roundish, 2—3-dentate lobes, the teeth spinulose.