The English flora - SeaweedAfrica

186 LICHENES. [Lecanora.
convex without a border. Sm—Patellaria ulmicola, DC—
Lecidea luteo-alba, Ach. Syn. p. 49. Lichen luteo-albus, Turn,
in Linn. Trans, v. 7. p. 92. t. S.f. 3. E. Bot. t. 1426.
On the bark of trees, in various parts of England.
67. L. aurantiaca, Ach. (saffron-coloured Lecidea); crust
granulated whitish-lemon-coloured, apothecia sessile rather
convex orange- coloured with a yellow waved border. Sm—
Ach. Syn, p. 50 Lichen aurantiacus, Light/.—Lichen sali-
Lecanora salicina, Ach. Syn.
cinus, Schrad E. Bot. t. 1305.
— — —
p. 175.
On the trunks of trees, especially of Willow and Poplar.—Mr. Borrer
has determined this to be the Lichen aurantiacus of Lightfoot, whose
older appellation I consequently prefer.
68. L. erythrella, Borr. Mss. {orange Stone Lecidea); crust
lemon-coloured thin dispersed in minute angular smooth fragments,
apothecia sessile deep orange with a lighter border at
length .becoming nearly globose and the border obliterated. Sm.
—Lecanora erythrella, Ach. Syn. p. 175. Lichen erythrellus, E.
Bot. t. 1993.
On rocks and stone-walls : not unfrequent in the Highlands of Scotland.—
Mr. Borrer thinks it is scarcely distinct from the preceding.
14. Lecanora. Ach. Lecanora.
Thallus crustaceous, spreading, plane, adnate, uniform. Apo-
thecia (patellulcc) orbicular, thick, sessile and adnate, the disk
plano-convex, its border thickish, formed of the crust and of the
same colour.—Name ; Xzkxhcv, a small shield, and wga, form ;
from the form of the apothecia.—Our valued and learned friend,
Mr. Borrer, says he adopts the Genus Lecanora with reluctance,
as distinguished by an unsatisfactory character from Parmelia. But
surely inhabit should be considered together with the structure of
the thallus or frond (and without it our arrangement of Cryptogamiae,
in particular, would be most incongruous,) the greater
number of the Acharian Lecanora with their crustaceous fronds
and the almost leafy or coriaceous Parmelice ought to be separated.
Still I must agree with that eminent Lichenist, that the
limits of this, as of almost all the Genera of Lichens, are not
easily defined. There are connecting links, and the place of
such must perhaps ever remain doubtful.
* Apothecia black or dark brown, sometimes pruinose.
1. L. dtra, Ach. (black-shielded Lecanora); crust subdeterminate
rugged slightly cracked granulated and white, apothecia
nearly flat deep-black the border elevated white at length
Lichen ater, E. Bot.
notched and flexuose Ach. Syn. p. 146.
t. 949.
Common on walls and rocks.
2. L. argopholis, Ach. (white-scaled Lecanora); crust smooth
rugged and wartecl pale the warts at length imbricated some-