358 LICHENACEL. [LEcANORA, 
structure of the spermogones, The thallus, which is of moderate size, is 
often thinly white-pruinose, especially towards the centre, but becomes 
citrine when moistened. The apothecia, which are chiefly central, are in 
age subbiatorine. The spermogones have the spermatia 0,003 mm. long, 
0,001 mm. thick. 
Hab. On calcareous soil, shell-sand, and in the crevices of rocks in 
mavitime tracts.—Distr. Local, thongh not uncommon where it occurs in 
the Channel Islands, 8. England, and 8. Wales.—B. M.: Quenvvis, 
Island of Jersey ; Island of Guernsey. Freshwater Bay, Isle of Wight ; 
Newhaven and Rottingdean Cliffs, Sussex; Bray Hill, St. Minver, 
Cornwall; Stackpole Court and Lydstep, Pembrokeshire. 
10. L. elegans‘ Ach. Lich. Univ. (1810) p. 485.—Thallus orbi- 
cular, appressed, stellato-radiate, thickish, orange- or tawny-red ; 
lacinie subdiscrete, multifid, convex, torulose (K+ purplish). Apo- 
thecia moderate, adnate, somewhat concave or nearly plane, conco- 
lorous (K+ purplish), the thalline margin entire ; spores ellipsoid or 
ovoid, 0,011-16 mm. long, 0,006-9 mm. thick.—Cromb. Grevillea, 
xviii. p. 44; Hook. Fl. Scot. ii. p. 50 pro parte —Placodium elegans 
Mudd, Man. p. 131, t. ii. f. 41; Cromb. Lich. Brit. p. 45; Leight. 
Lich. Fl. p. 178, ed. 3, p. 163. Squamaria elegans Sm. Eng. Fl. 
v. p. 195. Lichen elegans Link, Ann. Bot. i. (1794) p. 87.—This 
is the plant of most British authors only in so far as relates to the 
diagnosis (evidently borrowed from Acharius) given by them, the 
localities and habitats cited being chiefly erroneous. 
A beautiful lichen, somewhat resembling Physcia partetina vay. ectanea, 
but is of an Arctic or Alt-alpine type. From the other species of the 
subgenus it is easily recognized by the thallus being distinctly corticate 
on both sides. Elsewhere in Europe it is rather variable, presenting 
several well-marked varieties, of which only one has been met with in 
this country. The few British specimens seen are rarely fertile, the 
spermogones also being rare, with spermatia 0,003-4 mm, long, 0,101 
mm, thick. 
Hab, On granitic rocks in alpine situations.— Distr. Only very spar- 
ingly among the N. Grampians, Scotland—B. M.: Lochnagar and 
Cairngorm, Braemar, Aberdeenshire. 
f 
Var. f. tenuis Ach. Syn. (1815) p. 183.— Thallus small, thin ; 
Jacinie narrow, discrete. Apothecia small_—Cromb. Journ. Bot. 
1885, p. 195.—Lichen elegans 3. tenuis Wablenb. Fl. Lapp. (1812) 
p. 417. Lecanora elegans form minor Cromb. Journ. Linn. Soc. 
Bot. xvii. p. 571. Placcdium elegans (3. discreta (Scher.), Mudd, 
Man. p. 181. Lichenoides tenuissimum, scutellis exiguis miniatis 
Dill. Muse. 175, t. 24. £. 68. 
Differs in the much smaller thallus, the nayrower subfiliform discrete 
radii, and the smaller apothecia. In most British specimens the thallus is 
minute, with the 1adii somewhat scattered, and very sparingly fertile. 
Hab. On calcareous rocks in subalpine situations Distr. Very local 
and searce in 8, Wales, N. England, and among the N. Giampians, 
ScotJand.—B. M.: Whimbold Rocks, near New Radnor, Radnorshire ; 
East Allendale, Northumberland. Craig Guic, Braemar, Aberdcenshive. 
