364 LICHENACEI. [LECANORA. 
effigurate at the circumference, bright-yellow or orange-red (K+ 
purplish). Apothecia minute, numerous, plane or convex, con- 
colorous (K+ purple), thalline margin entire; spores 0,010-14 mm. 
long, 0,005-6 mm. thick.—Cromb. Grevillea, xviii. p.45.— Placodium 
murorum B. lobulatum Mudd, Man. p. 132; Cromb. Lich. Brit. p. 45. 
—Var. obliteratwm (Pers.) Leight. Lich. Fl. p. 176, ed. 3, p. 161.— 
Brit. Exs.: Leight. n. 268; Cromb. n. 156; Larb. Cesar. n. 74; 
Lich. Hb. n. 295. 
Distinguished from all the preceding species by the less developed and 
almost non-radiate thallus. In a young state it is orbicular and slightly 
etfigurate, but becomes indeterminate (often spreading extensively), with 
the peripheral radii indistinct. When the colour is more miniate, it is 
Lichen obliteratus Pers. Ust. Ann. Bot. ii. p. 15 (mintatus auctorum pro 
parte). The apothecia are very numerous and crowded, usually almost 
obliterating the thallus, becoming at length convex and immarginate. 
The spermogones have the spermatia oblong, 0,002-3 mm. long, 0,0005-7 
mum. thick. 
Hab. On rocks in maritime districts —Distr. Here and there through- 
out Great Britain, Ireland, and the Channel Islands; very abundant on 
the coast of Kincardineshire——B. M.: Rozel, Island of Jersey ; West 
Coast of Guernsey; Island of Alderney. Ilsham, Torquay, Devonshire ; 
St. Maws, Cornwall; North Cliff, Tenby, Pembrokeshire ; Southerndown, 
Glamorganshire; Barmouth, Merionethshire; Island of Anylesea; 
Douglas, Isle of Man; St. Bees, Cumberland ; Arnbarrow, Westmore- 
land. med Argyleshire ; Portlethen, Kincardineshire; Peterhead, 
Aberdeenshire ; Applecross, Ross-shire. Upper Lake, Killarney, co. 
Kerry ; Ardglass, co. Down. 
16. L. scopularis Nyl. Flora, 1883, p. 105.—-Thallus orbicular, 
somewhat small, firm, naked, radiately divided at the circumference, 
verrucoso-arvolate in the centre, vitelline ; radii narrow, contiguous, 
convex (K + purplish). Apothecia small, numerous, plane, con- 
colorous (K + purple), the thalline margin entire ; spores 0,009-0,017 
mm. long, 0,005-7 mm. thick.—Cromb. Journ. Bot. 1885, p. 195. 
Approaches L, lobulata, but differs especially in the distinctly placodioid 
thallus. In the single fertile British specimen seen, the apothecia are 
numerous, with the thalline margin persistent. The spermogones are 
rarely present, with spermatia oblong, about 0,0025 mm. long, 0,0005 
mm. thick. 
Hab. On schistose rocks in a maritime district—Distr. Found only 
very sparingly in N.E, Scotland.—B. M.: Portlethen, Kincardineshire. 
17. L. miniatula Nyl. Flora, 1883, p. 98.—Thallus small, 
orbicular, plane, closely adnate, thinly rimoso-areolate, slightly 
subeffigurate at the circumference, deep tawny-vermilion-coloured 
(K + purplish), Apothecia minute, concolorous (K + purple), the 
thalline margin entire; spores 0,007-10 mm. long, 0,004-5 mm. 
thick.—Cromb. Journ. Bot. 1885, p. 195. 
Subsimilar to Z. lobulata (obliterata), but differs in the subeffigurate 
thallus, the smaller apothecia, and more especially in the smaller spores. 
It probably, however, descends from subsp. LZ. tegularis, of which it 
