400 LICHENACEI, [LECANORA. 
marginate, brownish-black ; spores broadly ellipsoid, very obtuse at 
the apices, with a broad transverse septum, 0,016-20 mm. long, 
0,008-12 mm. thick; paraphyses not very discrete, brownish at the 
clavate apices ; hymenial gelatine bluish, the thecee violet-coloured, 
with iodine.—Cromb. Journ. Bot. 1875, p. 141; Leight. Lich. FI. 
ed. 3, p. 220.—Psora Bischoffii Hepp, Lich. Europ. (1853) n. 81. 
Well distinguished from the allied species by the broad septum of the 
spores. In our few British specimens the thallus is little visible, but the 
apothecia are numerous. When these are immarginate the plant has 
entirely a lecideine appearance. 
Hab. On calcareous rocks in upland situations.— Distr, As yet only in 
W. England and the Central Grampians, Scotland; no doubt overlooked 
elsewhere.—B. M.: Rodmarton and Stroud Read, Gloucestershire; En- 
nerdale, Cumberland. Craig Tulloch, Blair Athole, Perthshire. 
Var. 3. immersa Cromb. Journ. Bot. 1876, p. 360.—Thallus 
evanescent. Apothecia foveolato - immersed, somewhat plane, 
blackish, the margin brownish, involute.—Leight. Lich. Fl. ed. 3, 
p. 221.— Rinodina Bischoffii 8. immersa Koerb. Par. Lich, (1865) 
p. 75. 
A rather inconspicuous plant, differing from the type in the immersed 
apothecia, with their usually involute margin. The thallus is generally 
contused with the stone, but when visible it is whitish and macular, 
Hab. On calcareous rocks and walls in hilly tracts—Dz¢str. Local 
and scarce in S.W. England.—B. M.: Yatton and Weston-super-Mare, 
Somersetshire. 
70. L. colobina Ach. Lich. Univ. (1810) p. 358.—Thallus sub- 
determinate, thinnish, granulato-pulverulent, casio-greyish or 
greyish-black (K+ purplish). Apothecia minute, adnate, somewhat 
plane, blackish ; the thalline margin entire, thickish, casio-greyish ; 
spores oblongo-ellipsoid, sometimes slightly constricted in the middle, 
0,016-20 mm. long, 0,007-9 mm. thick ; epithecium K + purplish.— 
Cromb. Journ. Bot. 1882, p. 273.—Brit. Hxs.: Larb. Lich. Hb. 
n. 91. 
A good species, readily distinguished from its immediate allies by the 
different reactions. In the single British specimen seen the thallus is 
leprose, dark, and the apothecia only sparingly present. 
Hab. On the trunks of old elms in a lowland district.—Distr. As yet 
only very sparingly in E. England; no doubt to be detected elsewhere. 
—B. M.: Near Cambridge. 
71. L. Conradi Nyl. Not. Sillsk. pro F. et Fl. Fenn. Forh. 
xi, (1871) p. 182—Thallus subeffuse, verrucoso- or subleproso- 
granulate, thinnish, griseous or greyish-brown (K—, CaUl—), 
Apothecia moderate, plane, blackish-brown, opaque, with the 
thalline margin rugulose or obsoletely crenulate, at length convex 
and immarginate; spores 4-locular, the cells nucleolate, 0,026-32 
