L I C H E N ferrugineus.
Rusty-shielded IAchen.
CRYPTOGAMIA Alga.
Gen. Char. Male, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
Spec. Char. Crust cracked, rugged, greyish white.
Shields rusty orange, at length convex, with a waved
notched margin of the same colour.
Syn. Lichen ferrugineus. Huds. 526.
L. aurantiacus. Lightf. 810.
L . crenularius. With. v. 4. 2 2 . t. 31. f . 5. Hull. 291.
L . caesio-rufus. Schrad. Spicil. 80. Ach. Prod. 45.
Patellaria cinereo-fusca. Hoffm. PI. Lich. t. 1 2 . f . 1 .
P. ferruginea. Hoffm. PI. Lich. t. 35. f . 1 .
Verrucaria ferruginea. Hoffm. FI. Germ. v. 2 . 177-
Lecidea csesio-rufa. Ach. Meth. 71.
B r it is h authors have been extremely confused about this
Lichen, nor have foreigners well understood it. We are persuaded
that the above synonyms are correct, and we think
Mr. Hudson’s original name by far preferable to the rest. His
quotations of Linnseus and of'Dillenius are indeed altogether
erroneous. We have already alluded to the species before us
at t. 845 and t. 1040 of this work.
L. ferrugineus grows on rocks and stones, as well as on the
bark of trees, in various places. Its crust varies in thickness^
but is more or less cracked and rugged, never mealy, of a
greyish white. Sometimes it assumes a kind of lead-colour,
and has a blackish edge. The shields are readily known by
their rusty orange hue, always uniform in the same specimen,
though specimens on sand-stones often have them of a dark
brown orange. Their disks are flat when young, mostly convex
when old. The margin is elevated, but not thick, soon becoming
elegantly waved and crenate, of the same colour as
the disk, or slightly brighter. The shields, being numerous,
often crowd one another into an angular figure.