PARMELIOPSIS. | PARMELIEI. 263 
1. P. ambigua Nyl. Not. Sallsk. pro F. et Fl. F. Férh. n. ser. v. 
(1866) p. 121.—Thallus stellato-orbicular, appressed, closely adnate, 
imbricato-laciniate, opaque, straw-coloured, sulphureo-sorediate ; 
beneath brownish-black; laciniz somewhat narrow, plane, multifid 
(K_, CaCl—). Apothecia small, plane or slightly convex, the 
margin entire or obsoletely crenulate; spores oblong or ovoid- 
oblong, often somewhat curved, 0,007-11 mm. long, 0,0025-35 mm. 
thick.—Cromb. Lich. Brit. p. 37.—Parmelia ambigua Borr. Eng. 
Bot. Suppl. t. 2796 (two lower figs.); Hook. Fl. Scot. ii. p. 55; 
Sm. Eng. Fl. v. p. 37; Leight. Lich. Fl. p. 127, ed. 3, p. 118. 
Lichen ambiguus Wulf. in Jacq. Coll. iv. (1790) p. 239. Parmelia 
diffusa Mudd, Man. p. 103.—Brit. Evs.: Leight. n. 373; Mudd, 
n. 75; Cromb. n. 146. ‘ 
The thallus is not unlike that of Parmetia Mougeotu, and is more or 
less sprinkled with soredia, which are normally convex and often con- 
fluent. In this country the apothecia are rare. The spermogones, which 
are more frequent, are very minute, blackish, sparingly scattered, with 
spermatia 0,018-25 mm. long, 0,005 mm. thick. 
Hab. About the roots of fir trees, and occasionally on old fir pales, in 
wooded, upland, and mountainous districts.—Distr. Local, though common 
where it occurs, in S., Central, W., and N. England, N. Wales, the Central 
Highlands, Scotland; not seen from Ireland.—B. M.: Ightham, Kent ; 
Twycross and Gopsall Park, Leicestershire; near Oswestry, Shropshire ; 
Cwm Bychan, Merionethshire; Ingleby Greenhow, Yorkshire. Killin, 
Perthshire; Kinnordy, Forfarshire; Mar Forest, Braemar, Aberdeen- 
shire ; Larig Grue, Banffshire ; Rothiemurchus, Inverness-shire. 
2. P. aleurites Nyl. Flora, 1872, p. 248.—Thallus stellato-orbi- 
cular, closely appressed and adherent, laciniato-lobed, greyish-white, 
whitish pulverulento-sorediate ; beneath brownish-black, sparingly 
fibrillose; laciniza somewhat convex and rugoso-plicate in the 
centre, plane and linear at the circumference (K*¥*", Cacl—). 
Apothecia small or nearly moderate, concave or somewhat plane, 
brownish- or reddish-spadiceous, shining, the margin slightly crenu- 
late; spores oblong or fusiformi-oblong, usually somewhat curved, 
0,011-12 mm. long, 0,003-4 mm. thick.—Cromb. Journ. Bot. 1872, 
p- 234.—Lichen aleurites Ach. Prodr. (1798) p. 117. Parmelia 
ambigua Borr. Eng. Bot. Suppl. t. 2796 (two upper figs.). Par- 
melia hyperopta Mudd, Man. p. 91; Leight. Lich. Fl. ed. 2, p. 478, 
ed. 3, p. 119. 
Externally little different, except in colour, from the preceding. The 
thallus, which is sometimes dark-greyish, is sprinkled towards the centre 
with white, scattered, roundish soredia. In the very few British speci- 
mens there are only one or two small apothecia with subentire margin. 
The spermogones, also rarely present, have the spermatia 0,0023-30 mm. 
long, 0,0005 mm. thick. 
Hab. On the trunks of old firs near the roots and on old fir pales in 
mountainous districts.—Distr. Very local and scarce in the N. Gram- 
pians, Scotland.—B. M.: Glen Derry and Glen Dee, Braemar, Aber- 
deenshire; Larig Grue, Banffshire. 
