284 CYCLOCARPINEE [LECANORA 
Several names have been employed for this plant: Lichen rimosus 
Oed. Fl. Dan. iii. t. 468, fig. 3 (1769) is altogether doubtful, though 
adopted by Scherer (Enum. p. 71), and Dickson’s plant of that name 
is Rhizocarpon calcarewm. Withering’s figure of L. rwpicola almost 
certainly represents the plant, though the description is deficient and 
the habitat ‘on calcareous rocks” is wrong; it is antedated by Lichen 
sordidus Pers., which has been generally accepted by competent and 
critical lichenologists, and of which the diagnosis and habitat accord 
with this lichen. LL. glaucoma subsp. bicincta Nyl. var. lecideina 
Cromb. Monogr. i. p. 422 (1894) was recorded as L. swbcarnea var. 
lecideina Cromb. in Grevillea xviii. p. 68 (1890), and belongs to that 
species. It has a thinner, smoother thallus, gives a red reaction with 
potash, and no dise reaction with CaCl. -L. glaucoma f. cerulata 
Leight. seems also to be identical with that form. 
Hab. On siliceous rocks, boulders and walls in maritime and 
upland districts, chiefly mountainous.—Distr. General and common 
probably throughout the British Isles—B. M. Jersey; Guernsey; 
Sark; St. Minver and Penzance, Cornwall; Bolt Head, Devon; near 
Folkestone, Kent; Charnwood Forest and Bardon Hill, Leicester- 
shire; Malvern Hills, Worcestershire; Aberdovey and Barmouth, 
Merioneth; Pwllheli, Carnarvonshire; Anglesea; Long Mynd and 
Haughmond Hill, Shropshire; Ayton and Cliffrigg, Cleveland and 
Ribbledale, Yorkshire; Middleton-in-Teesdale, Durham; Swinhope, 
East Allendale, Northumberland; near Milnthorpe and Swindale, 
Westmoreland; Catterleen, Cumberland; New Galloway, Kirkeud- 
brightshire; Kyles of Bute; Barcaldine, Argyll; Killin, Perthshire ; 
near Dundee, Forfarshire; Portlethen, Kincardineshire; Craig Guie 
and Castleton of Braemar, Aberdeenshire; Kinsale, Cork; Lambay 
Island and Howth, Dublin. 
Form decussata A. L. Sm.—Thallus marked with black lines, 
probably due to the presence of some other lichen.—L. glaucoma 
f. decussata Cromb. in Grevillea xviii. p. 68 (1890) & Monogr. i. 
p. 421. 
Hab. On rocks in maritime and upland distri¢ts.— Distr. Sparingly 
in the Channel Islands, N. England and E. Scotland.—B. M. Chateau 
Point, Sark; Gunnerton Crags, Northumberland; near Dundee, 
Forfarshire. 
Form complanata A. L. Sm.—Thallus and apothecia in a 
uniform plane. Apothecia innate.—L. glaucoma f£. complanata 
Leight. Lich. Fl. ed. 3, p. 205 (1879) ; Cromb. ll. ec. 
Ezsice. Johns. n. 113. 
Hab. On slate rocks in maritime districts.— Distr. Sparingly round 
the coasts of Great Britain and S. Ireland.—B. M. Near Towyn, 
Pembrokshire ; near Berwick-on-Tweed; Ballachulish, Argyll. 
Form distans A. L. Sm.—Thallus thin, rather smooth, cracked. 
Apothecia few, scattered, rather small.—L. glaucoma f. distans 
Johns. Exs. n. 414 (1910). 
Hasice. Johns. n. 414. 
Hab, On quartzose rocks and stones.—Distr., Rare in N. England. 
—B. M. Whitehaven, Cumberland. 
