[ 1731 ]
LICHEN hymenius.
Wrinkled Ilollow-shielded Lichen.
CRYPTOGAMIA Algce.
Gen. Char. Male, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
Spec. Char. Crust cartilaginous, uneven, somewhat
polished, greenish grey ; at length extremely tumid
and uneven. Shields elevated, crowded, hollowish,
very irregular, black, with an fexcessively tumid
wrinkled notched margin o f the substance o f the
crust,
Svn. Lichen hymenius. Ach. Prod. 80.
L. pertusus. Wulf. in Jacq. Coll, v . 2. 181, t. 13.
f . 2. Schrad. Spicil. t. 1 . f . 5.
Thelotrema hymeneum. Ach. Meth. 133.
W e first received this from the late Mr. W. Brunton in
1801. It has been long known to Mr. Turner, and is not
very unfrequent on the barks of old oaks and other trees. We
have Hampshire specimens from Mr. Lyell and Mr. W. Borrer.
Wulfen took it for L. pertusus, t. 677, a mistake which the
accurate Schrader easily corrected.
It is remarkable for its extremely wrinkled and prominent
aspect, consisting of innumerable irregular crowded elevated
warts, each of which bears a blackish depressed shield, of the
most irregular figure, enclosed in a very thick, tumid, inflexed,
waved and notched margin, of the substance of the wart or
crust. The warts cut perpendicularly look like the grinders of
some quadruped. The crust spreads indeterminately, and is of
a dull greenish grey, white within.
Acharius has formed a new genus Thelotrema of this, L. pertusus,
inclusus, and a few other species, which bear their
shields in a sort of warts.