J b J [ 1850 ]
LICHEN pericleus.
lions'll Black-O shielded Lichen.
CRYPTOGAMIA Alga.
G en . C h a u . Male, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
S p e c . C h a r . Crust diffuse, thin, leprous, very white.
Shields convex, very black, roughish, with a white,
crenate, at length powdery, border.
S y n . Lichen pericleus. Ach. Prod. 78.
L. abietinus. Ehrh. Crypt. 166.
Parmelia periclea. Ach. MetJj,. 156.
F o u n d bv Mr. W. Borrer at Hurst-pierpoint, Sussex, and
by the Rev. G. R. Leathes at Livermere near Bury. It grows
sometimes on old posts or pales, sometimes on the bark of
firs, as in specimens from Acharius, Swartz and Ehrhart, all
which we have diligently compared, and have therefore presumed
to make a correction with regard to the latter.
VVe further presume that this is a very distinct and w'ell-
determined species, admirably defined by the eminent writer
first mentioned. The crust is very thin, spreading irregularly
without any well-marked border, pure white, not tar-
tareous nor powdery. We do not find upon ours those
brownish-green parasitical tufts mentioned in the Methodus
Lichenum, and which are visible on all our foreign specimens.
The shields are, in our English specimens, scarcely larger
than those of the exiguus; hut they are peculiarly black,
convex, and distinguished by being roughish, though they do
not stain the finger like those of L. inquinans, t. 810. Their
border is very white, crenate, becoming powdery by age, and,
as it were, mouldering away into the circumjacent crust.
P sA 11S08, P u& lithed. b v AaASowerinf,ZonJAn.