47. V. elachistophora Nyl. in Flora Ixi. p. 246 (1878).—
Thallns white, unequal, cracked (perhaps not proper). Perithecia
(parasitic 1) black, partly emergent, slightly depressed above ;
peritheciai wall black, e n tir e ; spores 8 in the ascus oblong-
ellipsoid, colourless, simple (or sometimes spuriously 1-septate),
0,007-8 mm. long, 0,0035 mm. thick ; paraphyses moderate ;
hymenial gelatine not tinged with iodine.—Cromb. in Grevillea
vii. p. 98 ; Leight. Lich. Fl. ed. 3, p. 454. Specimen not seen.
The presence of paraphyses would exclude this species from the
genus, but it requires further investigation.
Hab. On quartzose rooks.—B. M. Kylemore, Connemara, Galway
(the only locality).
48. V. conturmatula Nyl. in Flora Ixii. p. 222 (1879).—
Thallus indicated by greyish spots. Perithecia small, black,
depressed, subconfluent; peritheciai wall dimidiate ; spores 8 in
the ascus, ellipsoid or ovoid-ellipsoid (sometimes obsoletely
1-septate), 0,011-14 mm. long, 0,005-6 mm. thick ; hymenial
gelatine wine-red with iodine.—Cromb. in Grevillea vii. p. 29.
Nylander considers that the species is possibly parasitic. The
specimen in the herbarium of the British Maseuni is too small and
scanty for examination. Larbalestier states that only two small
specimens were met with.
Hab. On quartzose rooks in a stream associated with Lecanora
lacustris.—B. M. Near Glenoorbet, Connemara, Galway.
V. niveoatra Borr. in Fngl. Bot. Suppl. t. 2637, fig. 1 (1830),
and V. mollis Tayl. in Mackay Fl. Hib. ii. p. 97 (1836) recorded
respectively as Pyrenothea niveoatra Leight. Angioc. Lich. p. 67,
t. 29, fig. 1, and P . molUs Leight. I. c. t. 29, fig. 2, are the
spermogonial condition of other lichens. V. niveoatra has been
determined by Nylander (Lich. Env. Paris, p. 108 (1896), as
the spermogonial state of Opegrapha cinerea, a species not otherwise
recorded in the British Isles. I t has arcuate spermatia
measuring 0,012-16 mm. long, 0,001 mm. thick, and in this
respect alone differs from 0. vulgata, in which the spermatia are
0,014-16 mm. long, 0,0005 mm. thick (fide Nyl. I. c .); the two
species may therefore be considered as identical. A specimen of
V. mollis from Carig Mt., Kerry, has been determined by
Nylander as the spermogonial state of Opegrapha sp.
V. lithina Tayl. in Mackay Fl. Hib. ii. p. 92 (1836)
(non Ach.) on rocks from Derriquin, Kerry, has been determined
as Pyrenothea lithina Leight. Angioc. Lich. p. 68, t. 29,
fig. 3. P . lutea Leight Z. c. t. 29, fig. 4, collected on trees a t
Gopsal, Leicestershire, and P. sulphurea Leight. tom. cit. p. 69,
t. 29, fig. 5, on sandstone rocks, Niton, I. of Wight, are also,
judging from the descriptions and figures, spermogonial states of
lichens not determined.
106. THELIDIUM Massal. Framm. Lich. p. 15 (1855).
(PI. 42.)
Thallus variously crustaceous, uniform, sometimes wanting.
Algal cells Pleurococcus. Perithecia black, simple, superficial or
immersed ; paraphyses mucilaginous, soon disappearing ; ^ asci
usually somewhat large and saccate, 8-spored; spores ellipsoid or
ovoid, usually rather large, 2-4-celled, colourless or sometimes
brownish.
Spores l-sep>tate.
1. Th. pyrenophorum Koerb. Syst. Germ. p. 353 (1855) pro
parte, emend, (non Massal.).—Thallus greyish-white or -brown,
effuse, thin, slightly cracked when old, sometimes almost obsolete.
Perithecia rather large, semi-immersed or superficial, usually
depressed round the ostiole ; peritheciai wall thick, dimidiate,
the inner wall brownish ; paraphyses disappearing ; spores broadly
oblong, colourless or pale-yellowish, 1-septate, 0,020-32 mm. long,
0,010-18 mm. thick.—Th. Borreri Mudd Man. p. 296 (1861).
Verrucaria pyrenophora Ach. Lich. Univ. p. 285 (1810) ; V.
Dufourii Borr. in Engl. Bot. Suppl. t. 2791 (1831) (non DC.) ;
Tayl. in Mackay Fl. Hib. ii. p. 92 ; Leight. Angioc. Lich. p. 51.
V. Borreri Leight. tom. cit. p. 76, t, 22, fig. 4 (1851) & Lich. Fl.
p. 429 ; ed. 3, p. 459 ; Cromb. Lich. Brit. p. 112 pro parte.
From the similarity in the outward formation of thallus and
especially of the perithecia, when well developed apt to be confused
with Th. papulare and Verrucaria Dufourii.
Hab. On calcareous rooks.—Distr. Eare in Scottish Grampians
and W. Ireland.—E. U. Ben Lawers, Perthshire ; Morrone, Braemar,
Aberdeenshire; Clifden, Connemara, Galway.
2. Th. mesotropum A. L. Sm.—Thallus pale, thin, unequal.
Perithecia black, somewhat turgid, convex; ^ peritheciai wall
dimidiate; spores colourless, ovoid or ovoid-oblong, small,
1-septate, 0,012-17 mm. long, 0,005-6 mm th ick ; hymenial
gelatine wine-red with iodine.—Verrucaria mesotropa Nyl. ui
Flora Ixix. p. 419 (1866) ; Leight. in Ann. Mag. Hist. ser. 3,
xix. p. 408 (1867) & Lich. Fl. p. 431 ; ed. 3, p. 459 ; Cromb.
Lich. Brit. p. 115.
Hab. On subalpine rooks.—Eisir. Eare in hilly districts in W.
England and Wales.—E. M. Llanymynech Hill, Shropshire.
3. Th. immersum Mudd Man. p. 295, t. 5, fig. 123 (1861).
Thallus white, grey-ashy-white or pale-dirty-yellow, thin, ta r tareous
and somewhat farinose, sometimes determinate. Perithecia
black, deeply immersed and leaving pits in the rock,
depressed round th e ostiole ; peritheciai wall thick above, thinner
round the base ; spores colourless, ellipsoid, constantly 1-septate,
rather large, 0,025-38 mm. long, 0,012-17 mm. thick.— Verru-
caria immersa Leiglit. Angioc. Lich. p. 57, t. 25, iig. 2 (lo o l)