LICHEN candicans.
Whitish Radiating Lichen.
CRYPTOGAMIA Algae.
Gen. Char. Male, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
Spec. Char. Crust tartareous, thin, orbicular, plaited,
lobed and radiating at the margin, bright greyish
white. Shields clustered, greyish black, slightly
convex, with a plaited, elevated, white border.
Syn. Lichen candicans. Licks. Crypt, fa sc . 8. 15. 1. 9 .
f 5. With. v. 4 . 17. Hull. 2 8 9 .
L. epigeus. Ach. Prod. 1 0 5 .
Parmelia epigea. Ach. Meth. 191.
F ir s t observed by Mr. Dickson on rocks in Yorkshire, and
published by him in 1793. In the following year it was
described in Usteri’s Annalen, fasc. 7- p. 25, under the name
of L. melanocarpus, by the learned Persoon, who discovering
that name to be preoccupied, changed it in the same volume,
p. 155, to epigeus, and the latter is adopted by Acharius.
We might perhaps waive Mr. Dickson’s right of priority,
were the name given by him less eligible than the other; but
epigeus {growing on the earth) conveys an erroneous idea,
our plant being always found either on hard calcareous rocks
or on chalk, as observed by Mr. W. Borrer at Chedder, and
near Bristol, as well as on the chalky summit of Beachy head,
Sussex.
This is both an elegant and uncommon Lichen. Its thin
hard crust is not to be separated, without destruction, from
the rock, on which it forms roundish patches, about an inch
broad, of a brilliant blueish white, the external part being
plaited, lobed and radiating. The surface is smooth and hard.
Shields more or less crowded, sessile, round, flattish, greyish
black, with a neat, elevated, at length plaited or crisped
border, of the colour and substance of the crust.