greyish-white, often scarcely visible or entirely obsolete (Kf + y e l lowish,
CaCl — ) ; hypothallus indistinct. Apotheoia small, lecideoid,
th in ly margined, a t length convex, blackish or dark-brown, whitish
within : spores broadly ellipsoid, 0 ,0 1 6 -2 0 mm. long, 0,010-11 mm.
thiok ; hymenial gelatine deep blue with iodine.—Cromb. Grovillea,
xviii. p. 47.—Lecidea æquata Nyl. olim, Cromb. Jo u rn . Bot. 1874,
p. 149. Lecidea coniops var. ft. æquata Aoh. Lioh. Univ. (1810)
p. 171.
A rather inconspicuous plant, having, lilie others of this section, entirely
the appearance of a Lecidea, hut with gonidia intruded into the margin of
the apothecia. Tlie single small British specimen is quite typical and
well fertile.
Hah. On granitic rocks in a maritime locality.'—Histr. Only very
sparingly in S.AV. England.—B. AI. ; Near Penzance, Cornwall.
75. L. p o ly sp o ra Nyl. Not. Sallsk. pro E. c t El. Fenn. Forh. xi.
(1871) p. 182.—Thallus determinate, very th in , granulate-verrucose
or smoothish, whitish or greyish (K—,CaCl —). Apotheoia m inute,
adnate, brownish-black or blackish, a t first plane with th in concolorous
or paler margin, th en convex and immarginate ; spores
1 2 -2 4 næ , oblong or ellipsoideo-oblong, stra ig h t or slightly curved,
0 ,0 1 3 -1 6 mm. long, 0 ,0 0 6 -8 mm. thick ; paraphyses no t discrete,
yellowish-brown a t the subolavate apices.—Cromb. Grevillea, xviii.
p. 47.—Bin o d in a piolyspiora F r. fil. Nov. Act. Beg. Soo. So. Upsal.
ser. 3, vii. (1861) p. 226. Bin o d in a sophodes Koerb., Aludd, Alaii.
p. 142.
Looks like a small Lecidea, thougli, as the apothecia have gonidia intruded
into their margin, it is evidently a Lecanora, as is shown also by
the structure of the spermogones. From all the allied species it is well
distinguished by the polyspored thecæ.
Hab. On the smooth bark of an alder in a wooded mountainous
district.—Histr. Only very spariugly on one of the S. Grampians, Scotland.—
B. AI. : Craig Calliach, Perthshire.
76. L. isidioides Nyl. Além. Soo. Cherb. v. (1857) p. 115.—
ThaUus effuse, th in , subsquamuloso-stellate, whitish or greyish-
white ; squamules miuute, simple or divided, cylindrical or slightly
compressed, isidioid, th e divisions often slightly constricted (K +
yellowish, CaCl—). Apothecia small or moderate, plane, dull-
purplish or brownish-blaok, th e thalline margin tumid, entire or
somewhat crenulate ; spores oblong or ellipsoideo-oblong, 1-septate,
ocoasionaUy slightly constricted in the middle, brownish, 0,0 2 6 -3 0
mm. long, 0 ,0 1 3 -1 5 mm. th ick .—Cromb. Lich. Brit. p. 49 ; Leight.
Lioh. F l. p. 224, ed. 3, p. 214.—Borrera isidioides Aludd, Man.
p. 106. Parmelia isidioides Borr. Eng. Bot., Suppl. t. 2808.
A very interesting endemic species, well characterized by the peculiar
isidioid, stellate thaUus. In its general aspect it looks almost a Physcia,
and though placed here by Nylander probably constitutes a distinct
section of Lecanora. Tlie tliallus i.s rather scattered, greenish-grey when
moistened, usually but sparingly fertile; though in one corticolous fragment
the apothecia are somewhat numerous.
Hab. On mossy and naked trunks of trees in upland situations.—Distr.
Extremely local aud scarce in N. AVales, where it has not recently been
met with.—B. AI.: Cwm Bychan and Crafnaiit, Alerionethshire.
D. ThaUus placodioid. Apotheoia leoanorine; spores 8riie, ellipsoid,
ra re ly subglobose, simple, colourless ; paraphyses jointed.
Spermogones with simple or shortly jointed sterigmata and
cylindrical, moderate, s tra ig h t spermatia.
77. L. m e lan a sp is Aeh. Lich. Univ. (1810) p. 427 ; Nyl. Flora,
1873, p. 18, nota.—Thallus suborbicular, adnato, thinnish, areolate
or verrucoso-rugose in th e centre, radiato-laciniate a t th e circumference,
greyish or loaden-greyish, th e radii convex, multifid (K —,
CaCl — ). Apothecia small, appressed, plane, a t length convex, the
th allin e margin entire ; spores ellipsoid, 0 ,0 1 1 -1 3 mm. long,
0 ,0 0 8 -1 0 mm. th ic k ; hymenial gelatine bluish, then wine-red with
iodine.—Leight. Lich. El. ed. 3, p. 201.— Lecanora alpihoplaca var.
melanaspis Stirt. Scottish N a tu ralis t, iv. p. 28.
Differs from L. alphoplaca (AA’ahl.), the typical species of this section,
of which it has sometimes been made a variety, and which is not found
in Britain, in the negative reaction with K, among other distinctive characters
of the thallus and apothecia. I have, however, seen no Britisli
specimen, and regard it as of doubtful occurrence in the locality recorded.
Hab. On rocks in a mountainous region.—Distr. Said to have been
found in the S.W. Highlands of Scotland (Ben Brecht, .'Argyle.shire).
78. L. c irc in a ta Ach. Lich. Univ. (1810) p. 4 2 5—Thallus orbicular,
closely adnate, verrueoso-areolate in the centre, radiato-plicate
a t the circumference, greyish or greyish-white, the radii contiguous,
narrow, somewhat plane or convex (K — or + yellowish). Apothecia
smaU or submoderate, innate, a t first suburoeolate, th en plane,
brown or dark-brown, the thaUine margin th in , e n tir e ; spores eUipsoid,
0 ,0 1 1 -1 5 mra. long, 0 ,0 0 6 5 -8 5 mm. th io k ; hj'menial gelatine
bluish, th en reddish with iodine.— L . circinata Cromb. Lioh. Brit,
p. 4 9 ; Leight. Lich. Fl. p. 195, ed. 3, p. 179 : Hook. FI. Soot. ii.
p. 50. Squamaria circjnata Mudd, Alan. p. 1 3 0 ; Sm. Eng. Fl. v.
p. 196. Placodium circinatum Gray, Nat. Arr. i. p. 448. Lichen
cireinatus Pers.-in Ust. Ann. Bot. vii. (1794) p. 25, Eng. Bot. t.
1941.—A well-marked species, of whioh the type apparently does
no t occur in Britain, b u t only th e peculiar form subcircinata Nyl. in
litt., differing merely in th e thalline reaction (K + yellow, then
saffron-red). This being bu t a supplementary reaction, the plant
is not now regarded by Nylander as constituting a distinct species as
in Flora, 1873, p. 18, subsp. Cromb. GreviUea, xviii. p. 47.—Lichen
2 d 2