The English flora - SeaweedAfrica

—
—
220 LICHENES. [Cctraria.
B. Upper and wider-surfaces of the thallus nearly alike.
a. Thallus usually compressed and laciniated. Apothecia scutelliform
(scutellm).
26. Cetraria. Ach. Cetraria.
Thallus foliaceous, cartilagineo-membranaceous, ascending- and
spreading, lobed and laciniated, on each side smooth and naked.
Apothecia orbicular, obliquely adnate with the margin of the
thallus, the lower portion being free, (not united with the
thallus); the disk coloured, plano-concave, with a border formed
of the thallus and inflexed.—Named from cetra, an ancient
buckler made of hide, which the apothecia are supposed to resemble.—The
species are eminently northern or alpine plants.
1. C. juniperina, Ach. (golden Cetraria); thallus pale yellow
deeper beneath, the segments plane ascending erose crenate and
crisped, apothecia elevated bright-bay the border crenulated.
Ach. Sy?i. p. 226.
— .
Lichen juniperinus, Linn.— (3. pinastri ;
thallus with the segments depressed bluntly lobed crenate the
margins crisped pulverulent very yellow. Ach. Syn. 1. c.—
Lichen pinastri, Scop.—Dicks—E. Bot. t. 2111 L. juniper-
inus, Lightf.
On trunks of trees. /3. in the north of Scotland, principally on
the Scotch Fir. Frequent about Aviemore, and at Kinnordy, the Seat
of Chas. Lye/l, Esq. Park pales at Framingham, near Norwich, Mr.
Turner.— The. fructification, though I have gathered it not unfrequently
—
in Switzerland, has, I believe, never been found in Britain.
2. C. sepincola, Ach. (Fence Cetraria); thallus olive-brown
paler and pitted beneath the segments flattish ascending lobed
waved subcrenate powdery, apothecia nearly marginal elevated
chestnut-coloured with a crenate and wrinkled border. Ach.
Syn. p. 227. Lichen sepincola, Ehrh.—Hedw. Cr. v. 2. p. 8.
t. 2. E. Bot. t. 2386.
On trees, mostly Firs and Birch, Scotland, especially in the north
Highlands. Kinnordy, Forfarshire. On old posts and rails by the sea,
near Yarmouth, Mr. Turner.—The apothecia are very rare.— Mr. Dickson
mentions this plant as growing upon stones in the Scotch moun-
-. tains I
have never seen it except on wood.
3. C. glduca, Ach. (glaucous Cetraria); thallus membranaceous
smooth somewhat shining sinuated and lobed glaucous-grey
above brown beneath, the segments cut and jagged curled ascending,
apothecia marginal elevated chestnut-brown, their border
wrinkled. Ach. Syn. p. 227. Lichen glaucus, Linn—
(3.fallax; thallus
—
E.Bot.t. 1066—ZW/. dfusc. t. 25. f. 46
white or glaucous on both sides or partially black beneath.
Ach. I. c.— C. fallax, Ach. Meth. p. 206.—Lichen fa llax, Web.
—Dicks. Cr. Fasc. 1. p. 13. E. Bot. t. 2373.—Dill. Muse,
t. 22. f. 58.
Heathy places on the ground, on rocks and trees ; not uncommon
—
—