The English flora - SeaweedAfrica

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160 LICHENES. [Pertumria.
7. Pertusaria. Ach. Pertusaria.
Thallus cartilagineo-membranaceous, spreading, adnate, uniform.
Apothecia verruciform, formed of the thallus, one-or
many-celled, each cell containing a nucleus, opening by a depressed
pore.— Named from pertusus, full of holes; in allusion
to the pores or depressed points in the wart, like excrescences
of the thallus.
1. P. communis, DC. {common Pertusaria); crust greyishwhite
smooth, warts of the apothecia crowded subglobose with
many depressed points. De Cand. Fl. Fr. ed. 1. p. 330.
Forma pertusa, Ach. Syn. p. 109. Lichen pertusus, Linn.—
E. Bot. t. 677.—Schcer. Lich. Helv. p. 64. n. 118.
On trunks of trees, abundant.
2. P. ceuthocdrpa, {cream-coloured Pertusaria); crust calcareous
continued cream-coloured tessellated unequal smooth,
warts of the apothecia tumid globose smooth with black depressed
points. Lichen ceuthocarpus, E. Bot. t. 2372.
On slate rocks in Ireland, where it grows in large uninterrupted
patches, Miss Hutchim and Sir T. Gage.— This has a cracked or tessellated
crusty fewer, more globose warts, and larger dots than P. communis.
3. P. fallax, Ach. (doubtful Pertusaria); crust somewhat
spreading plicato-rugose grey, warts of the apothecia crowded
irregular depressed above bordered by the swollen almost
gibbous and wavy circumference, pores solitary or many large
somewhat confluent distorted black. Porina fallax, Ach. Syn,
p. 110.— Verrucaria fallax, " Pers."—Pertusaria Widfenii, De
Cand. Thelotrema hymeneum, Ach. Meth.—Lichen hymenius, Ach.
Prodr.—E. Bot. t. 1731.
Not^infrequent on the bark of old Oaks and other trees.— Sir James
E. Smith compares the warts of this species, cut perpendicularly, to the
grinders of some quadruped. There is, indeed, a peculiarly deformed
and distorted appearance about this plant ; and it is, along with two
other Pertusaria, four Variolarics, and two Isidia, (as forms of one and
the same species,) made synonyms to P. communis, by Sprengel, on the
authority of Meyer.— Mr. Borrer considers the present plant to rank
with the Thelotremata, as is evident from his remarks at the end of the
description of his T. Hutchinsice, E. Bot. Sujipl. t. 2652.
4. P. isidioides, (Isidium-like Pertusaria); "crust thick
tartareous frustuloso-areolate yellowish-brown, tubercles small
globose pale immersed in tumid roundish warts except the
darker slightly prominent apex."— Verrucaria isidioides, Borr.
in E. Bot. Suppl. t. 2622. f. 1.
Rocks, GlangarhT, near Bantry, Miss Hutchins.— " Acharius would,
perhaps, have placed this singular Lichen in his genus Porina : yet the
manner in which their apex usually emerges appears to point out a
closer affinity to the other Verrucaria. It is, in fact, one of the manylinks
which connect the Pyrenula: of Acharius with his Endocarpa."
5. P. crdssa, (thick Pertusaria); crust cartilaginous undu-
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