LECANORA. | LECANO-LECIDEEI. 375 
Subsp. 2. L. irrubescens Nyl. Flora, 1874, p. 318.—Thallus 
effuse, thin, scattered, tawny-yellow, at times subevanescent. Apo- 
thecia subminute, biatorine, sessile, becoming convex and immargi- 
nate, orange-red.—Cromb. Grevillea, xix. p. 60. 
Differs in the characters given of the thallus and apothecia, The only 
British specimen (fragmentary) is in Hb. Salwey s. n. Lecidea picta Tayl., 
which Scherer (Enum. p. 149) referred to his var. 8. rwbescens (non Ach.). 
It is, however, identical with that of Anzi, Lich. min. rar. n. 135, upon 
which Nylander founded this subspecies. 
Hab. On schistosé rocks in a mountainous district.—Distr. Seen only 
very sparingly from N. Wales.—B. M.: Near Barmouth, Merionethshire, 
31. L. crenulatella Nyl. Flora, 1886, p. 461.—Thallus subeffuse, 
thin, unequal, rimose, citrine-coloured (K+purple). Apothecia 
moderate, plane, zeorine, subconcolorous (K+ purple), the thalline 
margin when present finely crenulate; spores ellipsoid, polari-bilo- 
cular (the loculi moderate), 0,016-20 mm. long, 0,008-9 mm. thick. 
—Cromb. Grevillea, xviii. p. 45. 
Well characterized by the double margin of the apothecia. It comes 
near subsp. L. erythrella, but, as Nylander J. c. observes, is scarcely to 
be subjoined under this. The thallus is little visible in the single speci- 
men seen, but the apothecia are numerous and occasionally crowded. 
Hab. On quartzose rocks in a maritime district—Distr. Very local 
and scarce in N.W. England (Arnside, Westmoreland). 
32. L. ochracea Nyl. in Cromb. Lich. Brit. (1870) p. 46.— 
Thallus determinate, thinnish, continuous or obsoletely rimoso- 
areolate, ochrey-yellow (K+crimson). Apothecia small, sessile, 
biatorine, at first concave, then plane, tawny-saffron or orange- 
coloured (K+ purple), the margin thin, paler: spores ellipsoid, 
polari-bilocular, usually with longitudinal tube, 0,011—-12 mm. long, 
0,006-7 mm, thick.—Leight. Lich. Fl. p. 218, ed. 3, p. 208.— 
Callopisma ochraceum Mudd, Man. p. 188, t. 2. f. 43. Lecidea 
ochracea Scher. in Nat. Anz. 1819, p. 11. Lecidea icterica Tayl, 
Lond. Journ. Bot. 1847, p. 150 (fide Leight. 7. ¢.). 
Closely allied to LZ. aurantiaca, but distinguished among other cha- 
racters by the constantly biatorine apothecia and the smaller spores. 
The structure of the latter detinitely separates it from Z. tetrasticha Nyl., 
to which externally it is almost similar and for which it is often 
mistaken. It is usually limited by a more or less distinct whitish hypo- 
thallus, and is always well fertile. 
Hab. On calcareous rocks in waritime and upland tracts.—Distr. Very 
local and rare in S.W. England, 8. Wales, the S.W. Highlands of Scot- 
land, and ?S.W. Ireland.—B. M.: Hope Cove, near Kingsbridge, 8. 
Devon; Giltar Point, Tenby, Pembrokeshire. Island of Lismore, 
Argyleshire. 
33. L. ferruginea Nyl. Act. Soc. Linn. Bord. sér. 3, t. i. (1856) 
p- 322,—Thallus determinate or subeffuse, thinnish, areolato- or 
