m [ 2245 ]
L I C H E N rupestris*
Orange Rock Richen.
CRYPTOGAMIA Alga;.
G en. Char. Male,, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
Spec. Char. Crust thin, dispersed, greenish grey.
Shields sunk, flat, bordered; at length convex,
smooth, deprived of their border, reddish orange-
coloured.
Syn. Lichen ruj. estris. Ach. Procl. 4 3 .
Lecidea rupestris. Ach. JWeth. 7 0 . Winch, v. 2. 39.
Verrucaria rufescens. Hoffm. Pi. Rich. v. 1. 8 0 .
t. 17. ƒ. 1.
COMMUNICATED from walls at Beamish, Durham, by
Mr. Winch, who assures us his specimen has been compared
with some from Dr. Acharius. if the greenish or greyish interrupted
and often evanescent crust, drawn in our plate,
really belongs to the shields, which from Hoffmann’s own specimen,
as well as his and Acharius’s description, we dare not
deny, this species is abundantly distinct from L. calvus, t. 948,
whose crust is white, continued, hard and firm; but we have
specimens of the latter overrun with something exactly similar
to Hoffmann’s plant at least, and we scarcely know where to,
draw the line. Certainly, however, in the plant before us there
is no trace of the proper crust of calvus. The shields when
young are sessile or immersed, nearly flat, of a deep orange,
with a border of the same colour, which disappears by age,
and the disk becomes almost globular, exactly like the advanced
state of calvus, t. 948, but of rather a more vivid hue;
whereas the young shields of the latter are depressed, pitted,
and irregular, with scarcely any proper border, and of a paler
orange than in rupestris.
Scopoli’s rupestris is by far too vague and comprehensive to
be hazarded as a synonym, and the figure in FI. Dan. t. 825,
f . 2, has very little likeness to any thing with which we are
acquainted.