(1831). Segestrella thelostoma Leight. Angioc. Lich. p. 34, t. 15,
f. 2 (1851). Lecanora thelostoma Hook, in Sm. Engl. Fl. v.
p . 189 (1833).
Distinguished by the wide depression round the scarcely visible
ostiole, hence the resemblance to a Lecanorine apothecium.
Hah. On whinstone rooks.—B. M. Bgglestone, Durham.
109. GONGYLIA Koerb. Syst. Lich. Germ. p. 351 (1855).
(PI. 45.)
Thallus crustaceous, not corticated. Algal cells Pleurococcns.
Perithecia almost sessile, soft in texture, bright- or dark-coloured
with a poriform ostiole; paraphyses slender, f r e e ; asci 4-8
spored; spores acicular, straight or somewhat bent, colourless,
multiseptate.
A small genus, with representatives in North and Central Europe.
The ostiole is very distinct, and tends to widen out a t maturity,
causing the perithecia to become almost disciform.
1. G. viridis A. L. Sm.—Thallus bright-green when fresh,
thin, spreading. Perithecia numerous, shining-black when moist,
globose, slightly immersed a t the base, the ostiole very distinct,
becoming w id e r; peritheciai wall soft, black, ra th e r uneven on
the exterior, dimidiate, the inner wall dark blue-green; asci
elongate-clav'ate, bent a t the base, about 0,140 mm. long,
0,010-12 mm. thick ; paraphyses longer th an the asci, numerous,
thread-like ; spores narrowly fusiform acicular, somewhat abruptly
narrower upwards or blunt, gradually tapering towards the base,
colourless, multi-guttulate becoming multi-septate, 0,060-65 mm.
long, 0,002-3 ram. thick.
The thallus follows the inequalities of the soil, and thus shows a
somewhat granular surface ; it is nearly allied to G. sahuletorum, a
species found in Central Europe, but differs in the thallus and the
much longer spores.
Hah.—On sandy soil by the side of a p a th.—B. M. Near Horsley,
Surrey (the only locality).
110. MICROGLJINA Koerb. Syst. Lich. Germ. p. 388
(1855); emend. Lonnroth in Flora xli. p. 632 (1858). Thelenella
Nyl. in Maine et Loire Mem. Soc. Acad. iv. p. 62 (1858) ;
see also P a rt i. p. 15. (PI. 46.)
Thallus crustaceous, non-corticated. Algal cells Pleurococcus.
Perithecia simple, immersed or almost free, globose or conical ;
paraphyses persistent, branched; asci 2-8-spored; spores ellipsoid,
muriform, colourless or brownish.
1. M. modesta A. L. Sm.—Thallus whitish, thin, continuous
or somewhat cracked and unequal. Perithecia embedded in
small protuberances of the thallus, subglobose; peritheciai wall
soft and colourless a t the base, brownish upwards to dark-brown
round the ostiole ; paraphyses slender, distinct ; asci elongate-
clavate, 4-8-spored; spores ellipsoid, colourless, muriform, 0,019—
38 mm. long, 0,011-18 mm. th ic k ; spermogones with slender
bent spermatia, 0,018-32 mm. long, 0,001 mm. thick.— Verrucaria
modesta Nyl. in Bot. Not. 1853, p. 164 ; Leight. Lich. El. ed. 3,
p. 492. V. Carrollii Nyl. ex Cromb. Lich. Brit. p. 119 (1870);
Leight. Lich. Fl. p. 455 ; ed. 3, p. 487. Sphseromphale Carrollii
Mudd Man. p. 283, t. 5, fig. 115 (1861).
Hab. On trees.—Distr. Rare in S.AV. England and S. Ireland.—
B. M. Barnsley Park, Gloucestershire ; Rostellan, Cork.
2. M. isidioides A. L. Sm.—^Thallus yellowish-brown, smooth,
crustaceous, ra th e r thick, areolate, the areolæ crowded, convex.
Perithecia immersed in the areolæ, minute; peritheciai wall
brownish below, darker upwards, dark-brown towards the ostiole ;
paraphyses slender, persistent, conglutinate ; spores 8 in the
ascus (or fewer), ellipsoid-fusiform, colourless, then becoming
brown, muriform, rather large, 0,030-46 mm. long, 0,012-16
mm. thick.— Verrucaria isidioides Borr. in Engl. Bot. Suppl.
t. 2622, fig. 1 (1830); Carroll in Journ. Bot. iv. p. 25 (1866);
Cromb. Lich. Brit. p. 117; Leight. Lich. Fl. p. 454; ed. 3,
p. 486. Pertusaria isidioides Hook, in Sm. Engl. Fl. v. p. 160
(1833). Porina isidioides Tayl. in Mackay Fl. Hib. ii. p. 102
(1836). Endocarpon isidioides Leight. Angioc. Lich. p. 20, t. 6,
fig. 4 (1851). Dermatocarpon isidioides Mudd Man. p. 270
(1861).
Hab. On rooks.—B. M. Glengariff near Bantry, Cork (the only
locality).
3. M. corrosa Arn. in Flora Ixviii. p. 155 (1885).—^Thallus
whitish or dirty-white, warted or granular and dispersed or
obsolete. Perithecia minute, black, embedded in the swollen
thalline wares (when present), the upper p a rt protuding ; peritheciai
wall dimidiate ; paraphyses distinct, slender, loosely
coherent ; asci subcylindrical ; spores 8 in the ascus, ellipsoid-
fusiform, colourless, becoming muriform, 0,018-22 mm. long,
0,007-011 mm. thick.—Limhoria corrosa Koerb. Syst. Lich. Germ,
p. 376 (1855).
Var. nericiensis A. L. Sm.—Thallus and perithecia more
developed and larger th an in the species, internally similar.—■
Microglæna nericiensis Hellb. Nerikes Lafflora, p. 123 (1871).
The species has not been recorded in Britain. Both the specimens
were collected by H. B. Holl, and called by him Verrucaria dispersa.
The thallus is broken up into the small scattered warts that form
the bases of the perithecia ; the spores are at first simple, then
finally septate and muriform.
Hab. On rocks in alpine regions.—Distr. Eare in N. AVales and
the Scottish Grampians.—B. M. Cader Idris, Merioneth ; Ben Lawers,
Perthshire.