[ 1793 ]
y 2 y '
LICHEN citrinus.
Lemon-coloured Wall Lichen.
CRYPTOGAMIA Algce.
Gen. Char. Male, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
Spec. Char. Crust leprous, powdery, indeterminate,
bright lemon-coloured. Shields scattered, sessile,
minute, orange-coloured, with a pale y e llow, powdery
border.
Syn. Lichen citrinus. Ach. Prod. 7 3 .
L . candelarius. Abbot. 2 6 2 ?
Lichenoides. Dill. Muse. 1 3 6 . 1. 1 8 . / . 1 8 . B ?
Parmelia citrina. Ach. Meth. 179.
Verrucaria citrina. Hoffm. FI. Germ. v. 2 . 1 9 8 .
I t appears from the works of Acharius that he had never seen
specimens of this plant, but adopted it from Hoffmann, who
seems however, by his Flora, to have confounded it with vi-
tellinus, t. 1792. Most botanists have done the same, and
we are obliged to Mr. Turner for first explaining the species to
us, since which we have found no difficulty in distinguishing
it at any time.
This species is very common, and, in the wet months of
the early spring, very conspicuous and brilliant, on brick or
flint walls in Norfolk, and probably other places. Mr. Hailstone
has sent it on wood, from Yorkshire. The crust is
moderately thick, friable, powdery, cracked when dry, of no
determinate figure, and often irregularly dispersed, of a fine
lemon-colour. Shields not very copious, scattered, minute,
sessile and imbedded in the powder of the crust; their disk
flat, deep yellow or palish orange-coloured ; their border thick,
elevated, powdery and paler like the crust.
We are convinced of this being distinct from our Lepraria
jla va , t. 1350, as well as from L . vitellinus, t. 1792, the
texture of the crust being very different from both. Concerning
another suggestion of the learned Acharius, whether this
species may ever become his L. candelarius, t. 1794, we speak
with more diffidence, but we think it very improbable, that
being in every stage truly leafy or frondose, its fronds bearing
the shields.