432 LICHENACEI. [LECANORA. 
varia it at once differs in the leprose thallus, though in all other respects 
it nearly agrees with that species (Nyl. éz Jitt.). The margin of the young 
apothecia is leproso-pulverulent. 
Hab. On old beeches (near the roots) and on aged pines in wooded 
upland tracts.—Distr. Only a few localities in E., S., Central, and N. 
England, but plentiful in these —B, M.: Near Highbeech, Epping Forest, 
Essex; New Forest, Hampshire; near Buxton, Derbyshire; Overend, 
Egremont, Cumberland. 
118. L. expallens Ach. Lich. Univ. (1810) p. 374.—Thallus 
effuse, thin or thinnish, leproso-pulverulent, pale-sulphur-coloured’ 
(K+yellow, CaCl+ orange-red). Apothecia small, lecanorine, sub- 
innate, plane or slightly convex, pale-yellow or flesh-coloured, the 
thalline margin thin, pulverulent, at length obliterated ; spores 
ellipsoideo-oblong, 0,011-16 mm. long, 0,004-5 mm. thick.— 
Cromb. Grevillea, xviii. p. 69; Leight. Lich. Fl. p. 199 pro parte, 
ed. 3, p. 184 pro parte.—Lecidea expallens Sm. Eng. Fl. v. p. 181 
(exel. ‘on rocks”); Tayl. in Mack. Fl. Hib. ii. p. 127. Lepraria 
expallens Pers. fide Ach. l.c. Lecanora varia ¢. orosthea Mudd, Man, 
p. 150. Lichen vrostheus Eng. Bot. t. 1549.—Brit, Eas.: Larb. 
Lich. Hb. n. 216. 
Easily recognized by the colour of the leprose thallus, which spreads 
very extensively over the substratum. In more shaded habitats it is 
somewhat thicker, whitish-sulphureous, sterile, and might readily be 
taken for a “ Zepraria.” The apothecia, which are comparatively rare, 
are usually somewhat scattered, though at times several are subcon- 
fluent. The spermogones, which, however, are much more frequent in 
the following variety, have the spermatia 0,020-mm. long, 0,0009 mm. 
thick (fide Nyl. in litt.). 
Hab. On the trunks of trees, firs and oaks, and on old pales in lowland 
and upland districts.—Distr. Here and there throughout England and in 
N. Wales; rare in S.W. and N.W. Ireland; not seen from Scotland, 
though no doubt it exists there in a leprarioid state—B, M.: Thetford, 
Norfolk; Ickworth, Suffolk; Tetsworth, Oxfordshire; New Forest, 
Hants; near Newton Abbot, Devonshire ; Coleshorne and Oakley Park, 
Cirencester, Gloucestershire ; Upton, Worcestershire ; Dolgelly, Merio- 
nethshire ; Garn Dingle, Denbighshire; Island of Anglesea; Airyholme 
Wood and Ripon, Yorkshire; St. Bees, Cumberland. Ballynahinch, 
Connemara, co, Galway. 
Var. f. lutescens Nyl. Flora, 1872, p. 248.—Thallus minutely 
granulato-pulverulent. Apothecia numerous, crowded, at length 
convex, submoderate, sessile, with the thalline margin inflexed or 
excluded. — Cromb. Grevillea, xviii. p. 69.— Lecanora lutescens 
Cromb. Journ. Bot. 1878, p. 133 ; Leight. Lich. Fl. ed. 3, p. 164.— 
Patellaria lutescens DC, Fl. Fr. ii. (1805) p. 344.—Brit. Exs.: 
Cromb. n. 65, 
Differs from the type, with which it has usually been confounded, in 
the more granulose thallus, and the larger, sessile apothecia with epulve- 
rulent thalline margin. These are often so numerous as almost to ob- 
literate the thallus. 
