The English flora - SeaweedAfrica

Urccolaria.} \
—
LICHENES.
171
In this instance, only, so far as regards the present genus, do I differ
from the learned authors of the Lic/wnographia Britannica, by considering
this plant rather as a Variolaria than a Parmelia (Lecanora, Ach.).
Its crust and general habit, as Sir James E. Smith observes, are those
of Variolaria \iultipunctata, where the powder of the shields is very
deficient, and where the disk (lamina proligera) is very evident. Here
the disk is still more copious, the powder is entirely absent, and its place
is supplied, if I may use the term, by a white membrane, stretched
across the whole apqthecium. If, however, it be placed among the
LecanorcE it must rank with L. Parella.
12. V. argena, Turn, and Borr. (silvery Variolaria); crust suborbicular
between filmy and tartareous very thin rugulose grey
covered here and there in patches with white powder surrounded
by a white fibrous border, apothecia in scattered clusters orbicular
flattish with an inflexed border, powder white not abundant.
Turn, and Borr. Licit. Br. p. 75. Lichen argcenus, and
L. agelceus, (according to Ach.) Ach. Prodr. p. 8. E. Bot.
t. 1923, (bad).—Lecidea argccna, Ach. Meth. (not Syn.)—Thelotrcma
variolar hides, (3. Ach— Lichen farinosus, Hoffm.—
Lecanora verrucosa, Ach. Lich. Univ. p. 354.—y. Ach. Lich.
linr.p. 355.
On the bark of Lime and other trees, not uncommon.
13. V. agelcva, Turn, and Borr. (inelegant Variolaria); crust
elliptical almost filmy whitish surrounded by an obsolete border
of the same colour, apothecia very numerous depressed shapeless
crowded and becoming confluent so as to appear compound
with an inflexed border, powder white, the disk at length
bare blackish. Turn, and Borr. Lich. Br. p. IS.—Lich, „
agelceus, Ach. Meth.—E. Bot.t. 1720— Thelotrema variolarioidcs.
[3. agelcea, Ach. Syn. p. 117 Urccolaria agelcBO, Ach. Meth*—
Lecanora verrucosa, $. Ach. Lich. I inc. p. 355.
It will be seen by the synonyms of this and the preceding Lichen
what different opinions have been held, even by Acharius himself, rc-
Bpecting their generic and .specific identity. At length, in his Sunnpsis,
he has referred both of them to one and the same variety of Thelotrema
V. ageUea is ranked by Messrs. Turner and BoTfei
variolisriokk ,
among the Variolarics, on account of the presence of the powder in the
young and rigorous Btate of the plant ; mil thej still call it an "obscure
Lichen." T1h\ observe that it differs from V. argena aiul V. multipunctata,
in the thinner and more even thallus, and in the shape and
structure, as wdl as in the greater number, of its apothecia.—Some t
the figures '" /; - 1! "'- B PP car to mc to hears great resemblance to
Pertusaria communis.
—
e, Apothecia bordered, discoid, sessile (jxtfeltul
Pam. VI I. Leg inorv i .
Il\ I'k< BOL \ki \. Acht licrolaria.
ThaUus crustaceous, spreading, adnate, uniform. Apothecia
(patelluUe) orbicular, the dish concave, coloured, immersed in
of the crust ami of the Mune .-.dour.
the csust tin- bordi i formed