8. V. rhodosticta Tayl. I. c.—Thallus subtartareous, thin,
verrucose, the v e iT u c s e aggregate, purplish-black when dry, subgelatinous
and reddish when moist, minutely wrinkled ; perithecia
scattered, subglobose, scabrid. Specimen not seen.
Considered by Taylor as allied to the previous species, also referred
by Miiller-Argau (tom. cit. p. 551) to Pyrenopsis. The descriptions
of both species ar? too incomplete for accurate identification.
Hab. On wet rocks near Sheen Bridge, Kerry.
9. V. hydrela Ach. Syn. p. 94 (1814); Garovaglio Tent.
Disp. Meth. Lich. p. 22, t. 1, f. 2 (1864).—Thallus olivaceous or
olive-brown, effuse or determinate, smooth, thin or often thiokish,
gelatinous, becoming subtartareous, continuous, then somewhat
cracked, smooth, sometimes unequal. Perithecia moderate in
size, semi-immersed, the apex alone free, subglobose, b la c k ;
peritheciai wall dimidiate or continued below the base in a thin
lay er; spores ellipsoid, rather large, 0,019-26 mm. long, 0,008-
18 mm. thick.—Mudd Man. p. 285; Shackleton & Hebden in
Naturalist 1892, p. 17. V. Isevata Leight. Angioc. Lich. p. 44,
t. 19, f. 1 (1851) pro parte? V. elseomelsena Massal. in Atti.
Istit. Veil. 1857, p. 380, t. 5, figs. 1-4. V. margacea var.
hydrela Nyl. in Maine et Loire, Mem. Soc. Acad. iv. p. 26 (1858) ;
Cromb. Lich. Brit. p. 112. Lithoicea elseomelsena Massal. I. c.
Exsicc. Cromb. n. 198 (as V. elseomelsena).
Distinguished from allied species by the continuous unequal
thallus; the spores measure 0,012 mm. thick in the specimens
examined.
Hah. On rooks which are often under water.—Distr. Eare in
Central and W. England, and the Grampians, Scotland.—B. M. On
rocks in streams, Chedworth, Gloucestershire; Malvern, Worcestershire
; bed of the Wye, Buxton, Derbyshire.
10. V. Isevata Ach. Lich. IJniv. p. 284 (1810).—Thallus pale-
greyish-hrown, rather thick, tartareous, continuous or cracked-
areolate, whitish towards the edges and determinate with a dark-
coloured hypotballus. Perithecia immersed, the black shining
ostiole emerging; peritheciai wall entire, thickish ; spores 8 in the
ascus, ellipsoid, large, 0,018-24 mm. long or longer, 0,010-
11 mm. th ic k ; hymenial gelatine wine-red with iodine.—Borr.
in Sm. Engl. Bot. Suppl. n. 2623, f. 2 ; Hook, in Sm. Engl. El. v.
p. 153 ; Tayl. in Mackay PL Hib. ii. p. 91 ; Leight. Angioc. Lich.
p. 44, t. 19, f. 1 pro parte & Lich. Fl. p. 418; ed. 3, p. 449 ;
Mudd Man. p. 286.
Exsicc. Leight. n. 198 ; Mudd n. 273.
Closely allied to the preceding but distinguished by the more
tartareous deeply-cracked areolate thallus and the covered perithecia.
Hab. On rooks and stones usually in streams.—Distr. In upland
districts, rare in N. England, the Grampians, Scotland, and S. and
W. Ireland.—B. M. Craigforda and brook between Tugford and
Abdon, Shropshire ; Eiver Ithon, Llandrindod, Eadnorshire; Carnedd
Dafydd, Carnarvonshire; Airyholme Wood, Cleveland, Yorkshire;
Ben Lawers, Perthshire; Cork; Blaokwater Bridge, Killarney, Kerry.
Var. nigrata Leight. Lioh. PI. ed. 3, p. 449 (1879).—Tliallus
blackish-brown. Perithecia larger than in the species, immersed.
Hdb. On stones in running water.—B. M. Chedworth, Gloucestershire
(the only locality).
11. V. degenerascens Nyl. Ms. in Larb. Lich. Hb. n. 200.—
Thallus dark-brown, moderately thick, subdeterminate, mucilaginous
when moist, continuous, then irregularly cracked, not
distinctly areolate. Perithecia minute, semi-immersed, slightly
depressed round the prominent ostiole; peritheciai wall black,
entire, thick above, continued beneath the base by a thinner
lay e r; spores somewhat oblong, narrower a t one end, 0,017-
rarely -2 0 mm. long, 0,005-7 mm. thick.
Exsicc. Larb. Lich. Hb. n. 200.
Differing from V. Iwvata in the smooth superficially cracked
thallus and in the smaller spores.
Hab. On rocks.—B. M. Lough Feagh, Connemara, Galway (the
only locality).
12. V. margacea Wahlenb. Fl. Lapp. p. 465 (1812).—Thallus
olive- or greyish-brown, thin, smooth, somewhat shining, continuous,
effuse or determinate. Perithecia moderate in size,
immersed in the thallus, becoming emergent, opening by a pore,
the peritheciai wall dimidiate, or thinly developed under the base ;
spores ellipsoid or oblong, ra th e r large, 0,024-35 mm. long,
0,010-16 mm. th ic k ; hymenial gelatine wine-red with iodine.—
Cromb. Lich. Brit. p. I l l (excl. v a rs .); Leight. Lich. Fl. p. 416 ;
ed. 3, p. 446 (excl. vars.). V. suhnersa Borr. in Sm. Engl. Bot.
Suppl. t. 2768 (1833). V. Leightonii Hepp Flecht. Eur. n. 95
(1853) ; Mndd Man. p. 287 pro parte. Thelotrema margacea
Wahlenb. ex Ach. Meth. Supp. p. 30 (1803).
On moist rooks often about the margins of streams.—Distr.
Eather rare throughout the British Isles.—B. M. Trefriw Palls,
Bettws-y-Coed, Carnarvonshire; Craig Tulloch, Blair Athole and
Ben Lawers, Perthshire; Morrone, Braemar, Aberdeenshire; near
Ballinhassig, Cork ; Caher Mts., Kerry.
13. V. latehrosa Kmrb. Syst. Lich. Germ. p. 349 (1855).-—
Thallus reddish-grey, effuse, thin, faintly areolate. Perithecia
moderate in size, somewhat shining black, sessile more or less
covered a t the base by the th a llu s ; peritheciai wall dimidiate;
spores usually 8 in the ascus, large, ellipsoid, becoming slightly
brownish, 0,030—35 mm. long, 0,012—15 mm. thick. Leight.
Lich. PI. ed. 3, p. 448.
Exsicc. Larb. Lich. Hb. n. 237.
Nearly allied to the preceding but with a less gelatinous thallus
and more emergent perithecia.