convex ; hypotliallus very distinct, often predominating. Apothecia
plane or tumid, situated between the areolæ.—Mudd Man. I. c.
Lichen atrovirens L. Sp. PL p. 1607 (1753); Huds. FI. Angl.
ed. 2, p. 525 ; Lightf. I. c. ; With. I. c. Lecidea atrovirens Hook.
PI. Scot. I. c. ; S. F. Gray Nat. Arr. i. p. 465. Lecidea geographica
var. atrovirens Schær. Spicil. I. c. ; Oromb. Lich. Brit,
p. 93 & Journ. Linn. Soc. xxi. t. 9, f. 4 (1886); Leight. Lich.
FI. p. 346 ; ed. 3, p. 373.
Perhaps only a less developed thalline condition of the species.
When the areolæ are thinly scattered and the hypotballus predominates
it is f. protothallina Koerb. {I. o.). The spermogones are
more frequent than when the thallus is more developed, the
spermatia cjdindrical, nearly straight.
Hah. On rooks and boulders (calcareous excepted) in maritime and
mountainous districts.—Distr. No doubt similar to that of the species,
though seen from comparatively few localities, chiefly in Scotland.—
B. M. Eoughton, Cornwall ; Ben-y-gloe, Blair Athole, Perthshire ;
Portlethen, Kincardineshire ; Morrone, Braemar, Aberdeenshire ;
Hills of Appleoross, Eossshire ; Letter Hill, Connemara, Galway.
Var. lecanorinum Floerke ex Koerb. I. c.—Thalline areolæ,
somewhat discrete and convex. Apothecia immersed in the
areolæ, with a spurious margin ; spores usually halonate,
submuriform 0,030-40 mm. long, 0,011-16 mm. thick.—Lecidea
geographica var. cyclopica Nyl. Lich. Scand. p. 248 (1861); Leight.
Lich. FI. I. c. ; f. cyclopica ed. 3, p. 374.
Exsicc. Johns, n. 398.
Well distinguished by the soinewhat longer spores and by the
character of the apothecia, which are single in each of the areolæ and
appear as if lecanoroid from the spurious thalline margin.
Hab. On slate rooks.—Distr. Eare in upland or mountainous
districts in N. England and the Grampians, Scotland.—E. M.
Lakeside, Ennerdale, Cumberland ; Morrone, Braemar, Aberdeenshire.
Var. geronticum Th. Fr. Lich. Scand. p. 622 (1874).—Thalline
areolæ suhplane or convex, scattered or subcontiguous, somewhat
rugose, white, subpulverulent. Apothecia plane, immersed in
the areolæ.—Lecidea atrovirens var. gerontica Ach. Meth. p. 45
(1803). L. geographica var. gerontica Nyl. Lich. Scand. p. 248
(1861) ; Cromb. Lich. Brit. I. c. ; Leight. Lich. FI. p. 347 ; ed. 3,
p. 374.
Well characterized by the colour of the more or less pulverulent
thallus, whence Schærer (Spicil. pp. 124, 193) termed it var.
pulverulenta. It is rather interesting as being the only state of the
species which occasionally ooours on a calcareous substratum.
Hah.—On quartzose, occasionally calcareous, boulders and stones
in mountainous regions.—EisZr. Eare on the Grampians, Scotland.—
B. M. Morrone, Braemar, Aberdeenshire ; Ben Nevis, Eossshire.
7. Rh. viridiatrum Koerb. Syst. Lich. Germ. p. 262 (1855). ^
Thallus greenish-yellow, indeterminate, granular-areolate, the
areolæ discrete or crowded, K - , C aC l- , medulla I - ) ; hypo-
thallus little visible. Apothecia small, black, prominent, convex
and immarginate ; hypothecium blackish ; paraphyses coherent,
blackish a t the tips ; spores fusiform-oblong or ellipsoid, 3-septate
and soinetimes muriform, blackish, 0,018-25 mm. long, 0,009-11
mm. thick ; hymenial gelatine deep-blue with iodine—Bh. geographicum
var. sphsericum Mudd Man. p. 221. Lecidea viridiatra
Floerke Deutsch. Lich. iv. p. 4 (1819). L. geographica var.
sphaerica Schær. Enum. p. 106 (1850); f. spheerica Leight. Lich.
El. ed. 3, p. 373 (1879) ; var. viridiatra Leight. Lich. FL p. 347
(1871). _
Exsicc. Leight. n. 93 pro parte.
Distinguished from the preceding by the smaller spores and by the
absence of medullary reaction with iodine (hyphæ not amyloid). The
apothecia arise either from the hypotballus or from the areolæ.’
Hah. On rooks and boulders in hills and mountainous districts —
Distr Seen from only a few localities in England, Wales and
b. Ireland ; but no doubt to be detected also in S. Scotland.—A M
Malvern Hills, Worcestershire ; Llandegly, Radnorshire ; Haughm’ond
Hill and Longmynd, Shropshire; Cliffrigg, Cleveland, Yorkshire;
near Bantry, Cork ; Croghan, Killarney, Kerry.
_ 8._ Rh. caRareum Th. Fr. Lich. Arct. p. 236 (I860).—Thallus
thickish, white, orbicular, determinate, tartareous, cracked-
areolate in the centre, radiate a t the circumference ( K - ,
CaCl - ) ; hypotballus wanting. Apothecia immersed or depressed^
concave becoming plane, black, sontetimes slightly pruinose, the
margin thick, becoming thin and flattened ; hypothecium blackish-
brown ; paraphyses conglutinate, olivaceous or brownish towards
the apices ; spores ellipsoid or oblong-ellipsoid, obtuse, colourless,
then brownish or greenish-brown, large, muriform, with a distinct
hyaline epispore (halonate), 0,022-30-mm. long, 0,012-18 mm.
thick ; hymenial gelatine deep-blue with iodine.—Lichen calcarius
Weis PI. Crypt. Gott. p. 40 (1770). L. rimosus Dicks. Plant.
Crypt, i. p. 12 (1785) ; Engl. Bot. t. (1736) ? L. speireus Ach
Lich. Suec. Prodr. p. 59 (1798) ; Engl. Bot. t. 1864. Lecidea
speirea Ach. Meth. p. 52 (1803) ; S. P. Gray Nat. Arr. i. p . 468 ;
Hook, in Sm. Engl. El. v. p. 180 ; Tayl. in Mackay El. Hib. ii!
p. 125. L. contigua subsp. confluens f. calcarea Nyl. Lich. Scand.
p._ 225 (1861) ; Cromb. Lich. Brit. p. 80. L. rimosa Leight.
Lich. El. p. 350 (1871) ; ed. 3, p. 379. Diplotomma calcareum
Koerb. Syst. Lich. Germ. p. 220 (1855) ; Mudd Man. p. 219.
Exsicc. Johns, n. 397.
Hab. On calcareous rooks.—DZsZr. Not uncommon in maritime or
upland regions of the British Isles.—A. M. Downs and Newhaven,
Sussex; Llanymynech, Shropshire; Beddgelert and Snowdon, Carnarvonshire
; Llangollen, Denbighshire ; I. of Anglesea ; near Buxton,
Derbyshire ; Carlton Bank, Cleveland, Yorkshire ; Eglestone and
Teesdale, Durham; Hartside Fell, Cumberland; Achosragan Hill,
II . 0