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L I C H E N Perellus.
Crab' 's-eye Lichen.
CR T P TOGAMIA Alga.
Gen. Char. Male, fcattered warts.
Female, fmooth fhields or tubercles, in which the
feeds are imbedded.
Spec. Ch ar. Cruftaceous, white, granulated. Shields
of the fame colour, concave, with a thick blunt
border.
Syn. Lichen Parellus. Linn. Mant. 132. Hudf. 530.
With. v. 4. 1 y. Hull. 288. Relb. Suppl. x. 23.
Abbot. 262. Dickf. H. Sicc.fafc. 10. 23.
Lichenoides leprofum tin&orium, fcutellis lapidum
cancri figura. Dill. Mufc. 130. t. 18. ƒ. 10.
L. cruftaceum et leprofum, fcutellare, cinereum.
Raii. Syn. 70.
Patellaria Perella. Hoffm. PI. Lich. v. 1 . 60. /. 12
ĥ 5* _ _ _ _ _
-FO U N D on expofed rocks and ftones in mountainous countries,
fometimes on walls, fometimes on ftones by the fea fhore.
It forms white very confpicuous round patches, clofely adhering
to the ftone, but eafily fcraped off, various in thicknefs, with
a granulated, not powdery, furface, and a thin rugged very white
fpreading border. Shields copious, feffile, but prominent, of
the fame colour as the cruft, rather concave, with a thick elevated
fmoothifh margin. Occafionally their difk becomes convex
and warty.
This is the French Orfeille or Orchall, ufed for dyeing in
that country as L. tartareus, fee our t. 136, is in Scotland,
and prepared with volatile alkali in a fimilar manner, of which
a full account is given by Profeffor Hoffmann from a French
work of M. Amoreux of Montpellier, publifhed in 1787 by the
Academy of Lyons. The plant is more common in the fouth
of France than with us, and is called Perelle d’Auvergne, for
fo M. Amoreux directs us to fpell it, not Parelle, which laft
name belongs to fome fpecies of Rumex. Tournefort in his
Voyage mentions it by this name when he defcribes the
L. Roccella at the ifland of Amorgos. The colour furnifhed by
L. Perellus has rather more of a violet hue than that of L. tartareus,
but each is capable of being fo modified as to give any
tinge of purple or crimfon.