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LICHEN maurus.
Blackmoor Dot Lichen.
CRYPTOGAMIA Alga.
Gen. Char. Male, scattered warts.
Female, smooth shields or tubercles, in which th e
seeds are imbedded.
Spec. Char. Crust th in , continued, imperfectly circumscribed,
coal-black, smooth, with innumerable
minute cracks. Tubercles black, immersed, swelling
under th e crust, and marked by an umbilicated
dot.
Syn. Verrucaria maura. Ach. Meth. suppl. 1 9 .
F o u n d frequently on the Scottish coast, by Mr. W. Borrer.
Our specimen, taken by that gentleman from rocks near the seaside
at Dunbar, is on a reddish porphyritical stone or indurated
clay..
The crust is widely extended in continued very black patches,
without any marked or regular border; its substance thin, hard,
inseparable from the stone; the surface smooth, somewhat polished,
full of minute angular cracks. In the interstices of these
cracks are found numerous slight elevations of the crust, each at
length marked with a minute umbilicated depression. The tubercle
underneath never protrudes, but on dissection is found
imbedded in the crust, and of an intense black colour.