2._ L. flexella A. Zahlbr. in Engler & P ran tl Nat. Pflanzenf.
i. 1*, p. 93 (1903).—Thallus effuse, thin, whitish, or nearly
obsolete (K —, CaCl — ). Apothecia superficial, minute, black,
oblong or angular, the disc narrow and slit-like or irregularly
dilated ; hypothecium brown or blackish-brown ; paraphyses not
well discrete, dark a t the apices; spores 8 in the ascus, ovoid or
ellipsoid, minute, 0,004-6 mm. long, 0,002-3 mm. thick ;
hymenial gelatine bluish then sordid-wine-red with iodine. —
Limhoria flexella Ach. in Vet. Acad. Handl. 1815, p. 258.
Xylographa flexella Fr. Summa Veg. Scand. p. 372 (1849) ; Nyl.
in Mem. Soc. Sci. Nat. Cherb. v. p. 128 (1857); Cromb. in
Journ. Bot. xiv. p. 362 (1876); Leight. Lich. Fl. ed. 3, p. 392.
An aberrant species, allied to Xtjlographa, but with a dark
carbonaceous hypothecium.
Hab. On stumps of felled trees.—B. M. Oakley Park, near
Cirencester, Gloucestershire.
3. L. Andrewii Stirton in Scott. Nat. 1878, p. 300.—Thallus
indeterminate, thickish, subareolate, white or greyish-white
( K —, C aC l—). Apothecia small, sessile or innate-sessile,
roundish or oblong, simple or rarely divided, the margins
prominent, black, the epithecium becoming app lan a te; hypothecium
brownish; paraphyses slender, discrete; spores ellipsoid
or subglobose 0,008-9 mm. long, 0,005-6 mm. thick, with a
distinct epispore; hymenial gelatine not tinged, the asci tawny-
yellow, with iodine.—Leight. Lich. El. ed. 3, p. 394.
The apothecia in the single specimen seen are crowded ; Stirton
states that they are albo-velate in a young state.
Hab. On a granitic rock in an upland hilly d istric t.-B. M. Caiin
Edivard, New Galloway, Kiroudbrightshire (the only locality).
4. L. dendrographa Nyl. in Flora xlvii. p. 448 (1864).—
Thallus effuse, very thin, greyish (K - , CaCl - ) , subevanescent.
Apothecia ^ erumpent, linear, oblong or elliptical, simple or
slightly divided-furcate, black, concolorous w ith in ; epithecium
narrow, becoming applanate ; paraphyses slender, irregular, not
well discrete; hypothecium brownish-black ; ascus poly spored ;
spores ellipsoid, 0,005-8 mm. long, 0,003-4 mm. thick ; hymenial
gelatine wine-red with iodine.—Cromb. Lich. Brit. p. 95 ; Leight.
Lich. El. p. 361; ed. 3, p. 393.
In the British specimens the thallus is usually but little visible,
and becomes at length quite obsolete. The apothecia are numerous
and crowded, though at times somewhat scattered. When these are
simple the plant has very much the external aspect of a Hysterium.
Hab. On the trunks of old trees in maritime and upland tracts.
Distr.—Rather local and scarce in S. and S.W. England.—B. M. Near
Sidmouth, Cockington, near Torquay and the Dart, Devon : Swanase
Dorset; Whitefield, I. of Wight.
5. L. petræa Nyl. in Act. Soc. Linn. Bord. sér. 3, i. p. 393
(1856).—Thallus obsolete. Apothecia linear, simple, black,
slightly shining, gregarious, Often somewhat flexuose ; margins
tumid ; disc narrow ; hypothecium thick, black ; paraphyses
very slender, somewhat branched ; ascus polyspored ; spores
very minute, 0,003-4 mm. long, 0,001 mm. thick ; hymenial
gelatine pale-bluish, then wine-red with iodine.—Cromb. Lich.
Brit. p. 95, Leight. Lich. Fl. p. 360 ; ed. 3, p. 393. Opegrapha
petræa Dur. Exjil. Sci. Algér. p. 278 (1846) (excl. syn.)
(non Ach.).
Exsicc. Larb. Cæsar. n. 40.
Not to be confounded with Lecanora simplex, to states of which
it bears considerable resemblance, but differs in the lirelliform, congregate
apothecia and the black hypotheoium. The thallus is
indicated merely by a rudimentary dark hypotballus.
Hab. On rocks, in maritime districts.—Distr. Found only in the
Channel Islands and W. Ireland; no doubt to be detected elsewhere.
—B. M. Le Fret, Noirmont and La Moye, Jersey; near Kylemore and
Lettermore, Galway.
86. XYLOGRAPHA Er. Summa Veg. Scand. p. 372 (1849)
pro p a rte ; Nyl. in Mém. Soc. Sci. Nat. Cherb. iii. p. 187 (1855).
(Stictis § Xylographa Fr. Syst. Myc. ii. p. 197 (1823) emend.)
(PI. 23.)
Thallus developed under the bark (hypophloeodal). Algal
cells Palmella. Apothecia innate or erumpent, lirelliform, not
carbonaceous, roundish-oblong or irregular ; the disc plane or
concave ; hypothecium usually pale ; paraphyses slender ; spores
8 in the ascus, simple, colourless ; spermogones with simple
sterigmata and acicular curved spermatia.
Differs from Lithographa in the plane or concave apothecia and
ill the colourless or pale hypotheoium.
1. X. parallela Er. Summa Veg. Scand. p. 372 (1849).—
Thallus forming elongate whitish spots or little visible
(K —, CaCl — ). Apothecia innate, erumpent, black, narrowly
linear, straight, developed in parallel rows, a t first concave with
slightly elevated margin, becoming plane and immarginate ;
hypothecium colourless; paraphyses discrete, brownish a t the
apices; spores ellipsoid, 0,011-16 mm. long, 0,005-7 mm. th ick ;
hymenial gelatine bluish then violet-coloured with iodine.—
Cromb. Lich. Brit. p. 95 ; Leight. Lich. Fl. p. 362 ; ed. 3, p. 391.
Lichen parallelus Ach. Lich. Suec. Proclr. p. 23 (1798). Stictis
parallela Fr. Syst. Myc. ii. p. 197 (1822); Hook, in Sm. Engl.
Fl. V . 2, p. 213 (1836) ; Cooke Brit. Eung. p. 736 pro parte.
Exsicc. Cromb. n. 96.
Easily recognized by the peculiar arrangement of the fructification.
In the British specimens the thallus is but seldom distinct, being