p. 178; Tayl. in Mackay PI. Hib. ii. p. 122 ; Cromb. Lich. Brit,
p. 93 ; Leight. Lich. FI. p. 304 ; ed. 3, p. 316.
Exsicc. Larb. Lich. Hb. n. 146.
Has much the general aspect of more developed states of Bacidia
flavovirescens, of which it was subsequently regarded by Acharius as
a variety. Apart, however, from other characters, it differs in the
anatomical structure of the apothecia. In the British specimens the
thallus usually forms small orbicular patches. The apothecia are
numerous, often aggregate and confluent, arranged as it were in
circles.
Hab. On the ground, rarely encrusting mosses on rooks in mountainous
districts, generally associated with Boeomyces rufus.—Distr.
Very local and scarce on the Grampians, Scotland, and in W. Ireland.
—B. M. Ben Lawers, Craig Tulloch, and Rannoch, Perthshire ;
Canlochan, Forfarshire ; Morroño, Braemar, Aberdeenshire ; near
Kylemore, Connemara, Galway.
Form athallina A. L. Sm.—Thallus absent; apothecia pai-a-
sitic ; otherwise as in the type.—Lecidea scabrosa f. athallina
Nyl. ex Norrl. in Not. Sallsk. Faun. & FI. Fenn. n. ser. x. p. 341
(1873).
In one of the two British specimens there are traces of the proper
thallus, which probably is always normally present, though obliterated,
as in other instances, by the more vigorous growth of the host.
Hab. On the thallus of Boeomyces rufus in mountainous regions.
—Distr. Bare on the Grampians, Scotland.—B. M. Ben Lawers,
Perthshire ; Braemar, Aberdeenshire.
30. B. alpicola Krempelh. Lich.-Fl. Bay. p. 200 (1861).—
Thallus subdeterminate, thickish, areolate, the areolæ rather
large, continuous or somewhat scattered, plane or slightly
convex, bright-yellow (K + deep yellow, a t length orange-red,
CaCl — , medulla I —) ; hypotballus black, distinct. Apothecia
black, appressed, plane and thinly margined, a t length often
slightly convex, sessile, and immarginate ; hypothecium brownish-
black ; paraphyses concrete, black a t the apices, spores ellipsoid,
greenish - black, 0,018-28 mm. long, 0,010-15 mm. th ick ;
hymenial gelatine deep-blue with iodine. — Lecidea alpicola
Nyl. in Act. Soc. Linn. Bord. sér. 3, i. p. 388 (1856) ; Cromb. in
Journ. Bot. viii. p. 99 (1870) & in Crevillea iii. p. 143;
Leight. Lich. FI. p. 315 ; ed. 3, p. 328. L. geograpliica var.
alpicola Schær. Spicil. p. 124 (1828) & Enum. p. 106. L. atro-
virens var. alpicola Wahlenb. El. Lapp. p. 474 (1812) pro parte.
Externally subsimilar to states of Rhizocarpon geographicum,
with which, at flrst sight, it might readily be confounded. I t differs,
in the rather larger areolæ and apothecia, and more especially in the
1-septate shorter spores and the thalline reaction with hydrate of
potash. Apparently one of our rarer British lichens.
Hab, On quartzose and whinstone rooks and boulders in alpine
situations.—Distr. Very local and scarce on summits of a few of the
Grampians, Scotland.—E. M. Mael Graedha, Killin, Perthshire;
Morrone, Braemar, Aberdeenshire ; Ben Nevis, Invernessshire.
31. B. pulchella Tuckerm. Gen. Lich. p. 185 (1872).—
Thallus orbicular, thick, wrinkled, roundly lobed a t the circumference,
citrine-sulphureous or bright-greenish-yellow (K —,
CaCl — , medulla I — ) ; hypothallns black. Apothecia moderate,
appressed, plane, obtusely margined, a t length sessile, convex,
immarginate, black, concolorous within; hypothecium thick, black;
paraphyses coherent, yellowish-brown or sordid-greenish, dark-
brown a t the apices; spores ellipsoid, obtuse a t the apices,
often slightly constricted in the middle, brown, 0,010-17 mm.
long, 0,007—0,010 mm. thick ; hymenial gelatine bluish with
iodine.—Lichen pulcliellus Schrad. in Schrad. Journ. Bot. i. 74
(1801). L. galbulus Ramond ex DC. FI. Fr. ii. p. 368 (1805).
Lecidea pulchella Schær. Enum. p. 100 (1850); Leight. Lich.
El. ed. 3, p. 544. L. galbula Nyl. in Act. Soc. Linn. Bord.
sér. 3, i. p. 388 (1856); Cromb. Lich. Brit. p. 93.
Well characterized not only by the form of the thallus, but also
by its colour, which readily attracts the eye. In age, according to
Th. Fries (Lich. Scand. p. 588), the thallus becomes pulverulent
or rimulose. The apothecia are here and there confluent.
Hah. Incrusting decayed mosses on the ground in crevices of
boulders in alpine localities.—Distr. Extremely local and scarce on
one of the N.W. Grampians, Scotland.
32. B. colludens Tuckerm. Syn. N. Amer. Lich. pt. 2, p. 100
>88).—Thallus effuse or subdeterminate, areolate, the areolæ
plane or somewhat convex, scattered or contiguous, greyish-red
or brownish-grey, sometimes almost obsolete (K —, CaCl — , I — ) ;
hypotballus black. Apothecia rather large, sessile or innate-
sessile, plane, black, the margin thickish, entire, or rarely crenulate
; hypothecium brownish-black ; paraphyses conglutinate,
brownish-black a t the clavate apices; spores a t first colourless
then brown, ellipsoid or somewhat fusiform, with a hyaline
epispore, 0,018-29 mm. long, 0,007-14 mm. thick ; hymenial
gelatine deep-blue with iodine.— Lecidea colludens Nyl. in
Flora liii. p. 38 (1870) ; Cromb. in Journ. Bot. viii. p. 99 (1870) ;
Leight. Lich. El. p. 314. L. atroalba var. applanata Er. Summa,
p. 116 (1846). L. applanata Leight. Lich. El. ed. 3, p. 327
(1879) (non Chev.).
Exsicc. Larb. Lich. Hb. n. 355; Johns, n. 391.
The thallus varies in thickness and colour, and is sometimes
limited by the hypotballus. The apothecia are numerous, scattered or
contiguous, and sometimes slightly umbonate, with the margin usually
persistent, though occasionally they are convex and immarginate.
Hah. On schistose and quartzose rocks, usually by streams in
upland and subalpine districts. — Distr. Eather local in Central