Tayl. in Mack. Fl. Hib. ii. p. 142. Lichen microphyllus Eng. Bot.
t. 2128.—B rit. Eæs. : Cromb. n. 153.
Externally siibsimilar to P. micraphyVa, but differs m the less firm,
squamulose tliallus, and more especially in the infúscate hypothecium.
I t forms a thin or thiiniisli crust, with the squamules at A rf plane and
aduate on the hypothaUus, becoming at length granulose and diffract, the
squamules being visible only at the immediate circumierence. The
thallus varies somewhat in colour according to situation, hecommg more
or less blackish, whence form nigricans Leight. Lich. hi. ed. d, p. iOd.
The apotliecia are scattered aud occasionally darker in colour, but are
seldom present in our specimens.
Kah On the trunks of old trees in wooded upland districts. —Distr.
Somewhat local, though plentiful where it occurs in the mountainous
tracts of W. Britain and S.hV. Ireland.—B. M. ; Near Lydford, ®
Wood, and Lynton, Devonsiiire; St. Breock, Cornwall; Barmouth, Cwm
Bychan, and Harlech, Merionethshire ; Beddgelert, Carnarvonshire ;
Island of Anglesea. Kentmere, hVestmoreland. New Oallowa;^ lAirk-
cudbrightsliire ; Inverary, Barcaldine, and Appm, Argyleshire; Criaula-
rich, Loch Katrine, and Glen Lochay, I ’erthshire ; Craig Cluny, Braemar,
Aberdeenshire ; Glen Acli-iia-Shilloch, Ross-shire. Glen Bovvp W oods
and Glengariff, co. Cork; Turk Mt, and Dinish, Killarney, co. Kerry.
Var. ft. incrassata Nyl. ex Lamy, Bull. Soo. Bot. t. xxv.
p, 389.—Thallus thiok, densely coralloideo-stipate, brownish-hlack ;
hypothallus spongioso-rhizinose. Apothecia very ra re , ^ convex,
brownish-black.—Cromb. Grevillea, xviii. p. 44.— Pannaria tn p to -
plu jlla var. incrassata Nyl. Not. Sallsk. pro F. et Fl. F . Forh. v.
(1866) p. 124. Pannaria lasiella S tirt. Scot. Nat. iv. p. 164.
Distino-uished by the darker, much thicker thallus (4-6 mm. thick), and
by the p° cullar hypothallus. I t has only recently been met with in a
fertile condition.
Hab. On the trunks of old ash trees, rarely on mossy ground among
rocks, in upland wooded districts.—Distr. Local and scarce in the
ilio-hlands, and among the S. andN. Grampians, Scotland.—B. M. : Glen
Creran, Barcaldine, Argyleshire (fr t.) ; Glen Lochay, Kilhn, Perthshire.
4. P. nigra Nyl, ex Stiz. St. Gall. N a t. Ges. 1882, p. 336.
Thallus suhdeterminate, minutely coralloicleo-granuloso-crustaceous,
usually diffracto-areolate, thinnish, dark-greyish-blaok, brownish-
hlack or black ; hypothallus bluish-black. Apotheoia lecideine,
small, plane or slightly convex, black, in ternally pale-whitish, th e
margin entire, concolorous ; spores ellipsoid, 1 -septate (or simple
and oleoso-locular), 0 ,0 1 1 -1 8 mm. long, 0 ,0 0 5 -7 mm. th ick ; hypothecium
brownish-blaok,paraphyses th ic k ; hymenial gelatine deep-
hluish and th en dark-violet with iodine.— Cromb. Grevillea, xii.
p_ 58.—Pannaria nigra Cromh. Lioh. Brit. p. 43 ; Leight. Lioh. F l.
p. 168, ed. 3, p. 154. Lecothecium nigrum Mass., Mudd, Man. p. 175
pro parte. Collema nigrum Sm. Eng. F l. v. p. 207 ; Tayl. in Mack.
E l Hib. ii. p. 107. Placynthium n igrum Gray, Nat. A rr. i. p. 395.
Lichen nicjer Huds. Fl. Angl. ii. (1778) p. 524 ; W ith . Arr. iv. p. 10 ;
Eng. Bot. t. 1161.—B r it. Exs. ; Leight. n, 366.
Allied to P. triptophylla, of which it lias sometimes been considered as
a variety; hut it is specifically distinct by the less developed thallus, the
tvpe of the apotliecia, and by the spores not being definitely simple. The
tliallus, which forms a crowdedly diffracto-areolate crust, at times suh-
raniuloso-divided, is normally determinate, and is very distinctly limited
by a broad, conspicuous liypotliallus. Occasionally it is of a dark-brownish
colour, as are also the apothecia, whence var. ft fuscwm (Hepp.) Mudd,
Man. I. c. The apothecia are numerous, scattered or approximate,
sometimes becoming convex w ith evanescent margin.
Hab. On calcareous rocks, mortar of walls and flint pebbles, in maritime,
lowland, and upland tracts.—Distr. General aud common throughout
Great Britain, and no douht also in Irelan d ; rarer in the Channel
Islands.—B. M .: Gorey, Island of Jersey. Shiere, Surrey; Glynde,
Sussex ; Shanklin, Isle of W ig h t; Anstey’s Cove, Torquay, and Paington,
S. Devon; St. Minver, Cornwall; near Cromford and Buxton, Derbyshire
; near Stroud, Gloucestershire; Bathampton Downs, Somersetshire;
Llanymynech Hill and Bridgenortli, Shropshire; Barmouth, Merionethshire
; Eglestone, Durham ; Levens, Westmoreland; near Whitehaven,
Cumherland. Appin, Argyleshire ; Ben Lawers aud Craig Tulloch, Blair
Athole, Perthshire ; Castleton of Braeniar, Aberdeenshire ; Applecross,
Ross-shire. Near Belfast, co. Antrim.
Subsp. P. p so tin a Cromb. Grevillea, xviii. (1889) p. 44.—'Thallus
as in the type. Apothecia inte rn ally p a le ; spores oocasionally
3-septate (th e septa t h in ) ; hypothecium almost entirely colourless
(or p a rtly pale-brownish).— nigra subsp. psotina Nyl. ex
Cromb. jo u rn , Bot. 1873, p. 133. P. psotina Leight. Lioh. El. ed. 3,
p. 156. Pannaria nigra var. psotina kCa.,ficle Nyl. Lioh. Scand.
(1861) p. 126. Lecothecium nigrum Mudd, Man. p. 175 pro parte,
t. iii. f. 65 (middle fig'.).—B r it. Exs. : Mudd, n. 144.
Differs in the internal colour of the apothecia and in the spores being
rarely triseptate. In our specimens the thallus is subeffuse, with the
hypothallus rather narrow and at times little visible. In Flora, 1870,
p] 239, Nylander seems inclined to regard it as a proper species.
Hab On mortar of walls and calcareous rocks in maritime and lowland
districts.—Dlsri-. Only here and there in England and the Channel
Islands ; uo doubt to be detected elsewhere.—B. M .: The Vide, Island
of Guernsey. Eastbourne, Sussex ; near the Horse, Windsor Great 1 ark,
Berkshire; Bilsdale, Yorkshire. Hexham, Northumberland; Whitehaven,
Cumherland.
5. P. t r is e p t a ta Nyl. ex Cromh. Grevillea, xviii. (1889) p. 44.—
Thallus suhdeterminate, granuloso-orustaoeous, diffracto-areolate,
b rownish-blaok; hypothallus blackish, uot very distinct. Apotheoia
lecideine, small, th in ly margined, black or dark-reddish-
brown, internaUy w h itis h ; spores ellipsoid, 3-septate, 0 ,0 1 6 -2 3 mm.
long, 0 ,0 0 6 -9 mm. th io k ; hypothecium blackish or b row n ; _ hymen
ial ’ gelatine bluish w ith iodine.— Pannaria nigra var. triseptata
Nyl. Lioh. Soand. (1861) p. 126 ; Not. Sallsk. pro F . et Fl. F . Forh.
V. p. 1 2 5 ; Cromb. Lich. Brit. p. 43, subsp. triseptata Nyl. ex Cromh.
Grovillea, i. p. 171.