[ 965 3
CRYPTOGAMIA Alga.
G en. Char. Male, fcattered warts. Female, fmooth
fhields or tubercles, in which the feeds are imbedded.
S pec. Char. Cruft mealy, thin, white. Shields a
little elevated, brown, femi-tranfparent, with a
thick, elevated, even, fmooth, paler border.
Syn. Lichen corneus. With. v. 4. 2,0. /. 31. ƒ. 3.
Hull. 290.
■FIRST found by J. W. Griffith, Efq. on oaks at Gam near
Denbigh, and communicated to Dr. Withering, the only
writer (except Dr. Hull) who appears hitherto to have noticed
thisfpecies. We have received fine fpecimens from Egglefton,
Durham, by favour of the Rev. Mr. Harriman; Mr. W. Brun-
ton alfo has found it on oaks in Studley wood near Ripon. In
the more champaign parts of England it has not yet occurred.
The thin, mealy, white (or greenifh-white) cruft fpreads
clofely over the inequalities of the bark in fmall interrupted
patches. The fhields are pretty numerous, irregularly fcattered,
a little elevated on a fwelling, as it were, of the cruft, which
enfolds their bafe. They are fmall, nearly uniform in fize,
concave, of a brown horn-like colour, in fome degree tranf-
parent, efpecially the border, which is paler and rather waxy,
much elevated, fmooth and even.
With the greateft deference for Mr. Griffith’s opinion, whofe
accuracy and penetration we have experienced, we conceive
this plant, which fometimes grows mixed with Lichen pulicaris,
may have led him to fufpedt the metamorphofis of L. tricolor
(that is marmoreus) into pulicaris, fee With. v. 4. 23. The
fhields of corneus have in faft an occafional refemblance to
thofe of marmoreus when both are in decay.
9 & S