LICHEN fallax.
Fallacious Leafy Lichen.
CRYPTOGAMIA Alga;.
G en. C har. Male, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
Spec. Char. Membranaceous, smooth, glaucouswhite
on both sides, polished, lobed and finely
jagged. Shields terminal, slightly bordered,
brown ; at length dilated and convex.
Syn. Lichen fa lla x . Web. Goett. 2 4 4 . Ach. Prodr.
169. Dicks. Crypt, fa s c . 1. 13. W ith .v . 4. 5 3 .
H ull. 2 96.
L. alpinus membranaceus elegans, &c. Mich. Gen.
75. t. 37.
Lichenoides membranaceum, tubas fallopianae aemu-
lum. Dill. Muse. 165. t. 22. ƒ . 58.
Platisma fallax. Hoffm. PI. Lich. v. 2. 71. t. 46.
Cetraria fallax. Ach. Meth. 296.
S p e c im e n s of this very fine and rare Lichen were sent to
Mr. Dickson, many years ago, by Mr. Slater, who found
them on rocks in the mountainous part of Devonshire. Not
having been able to procure or even to see any of British
growth, we are obliged to rely, as we safely may, on such authority,
and to figure one given us by Prof. Gouan of Montpellier.
The present species is most allied to glaucus, t. 1606, from
which it differs in its more ample and diffuse form of growth,
more elegant and fringed divisions, large terminal dark-brown
shields, growing on elongated dilated segments of the frond,
and especially in its paler colour, which is, on the under side,
almost white, not brown or black.