LICHEN perforatus.
Perforate-shielded Lichen,
CRYPTOGAMIA Algce.
Gen. Char. Male, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
Spec. Char. Leafy, somewhat membranous, creeping,
veinless, lobed ; glaucous above ; black and
rough beneath ; crenate and fringed with black
hairs. Shields red-brown, at length perforated,
with an entire, smooth, narrow margin.
Syn. Lichen perforatus. Ach. Prodr. 155. IVulf.
in Jacq. Coll. v. 1. 116. t. 3 .
Lichenoides glaucum, foliorum laciniis crinitis.
Dill. Muse. 149. t. 20. ƒ. 4 2 . also ƒ. 43 and 44,
and t. 8 2 . ƒ. 3 .
Platisma perforatum. Hoffm. PI. Lick. v. 1. 6 5 .
t. 13. ƒ. 1. and t. 13 B ; figures all copied from
the above.
Parmelia perforata. Ach. Meth. 2 1 7 .
W e have many times gathered this Lichen in Wales, on
the trunks of old trees and on rocks, but could never find
shields. We have it of a very large size, like Dill. f . 43, but
still barren, from South America. Mr. W. Borrer sent the
annexed specimen from Sussex, where the plant is not uncommon
on trees and sand-rocks, but no fructification has been
discovered. The shields in our plate are from America.
Although nearly related to L.perlatus, t. 341, there is an
evident difference in the aspect of the present species, whose
edges are much more finely crenate or cut. The large pearly
marginal warts also are wanting, though the surface is here
and there granulated. The shields have a very thin smooth
and entire border, not an inflexed powdery or crenate one, and
they are very remarkable for acquiring a large irregular hole
in the centre, as soon as they advance towards maturity.