CETRARIA | PARMELIACE® 157 
somewhat rigid, pale-chestnut or dark-brown, alike on both 
surfaces, often stained a blood-red colour at the base, the fronds 
more or less regularly bordered with small spines and generally 
incurved, the lower side frequently dotted with white impressed 
decorticated spots (pseudo-cyphelle). Apothecia adnate on the 
upper surface of the apices, large or moderate in size, with a 
thin entire or crenulate disappearing margin ; spores 7—11] yp long, 
4-6 » thick.—S. F. Gray Nat. Arr. i. p. 433 ; Hook. Fl. Scot. ii. 
p. 58 & in Sm. Engl. Fl. v. p. 221; Tayl. in Mackay Fl. Hib. ii. 
p. 155 ; Cromb. Lich. Brit. p. 25; Leight. Lich. Fl. p. 96 ; ed. 3, 
p. 91. Lichenoides rigidum, Eryngii folia referens Dill. in Ray 
Syn. ed. 3, p. 77, n. 90 (1724) & Hist. Muse. p. 209, t. 28, 
f. lla. Lichen islandicus L. Sp. Fl. p. 11454 (1753); Huds. 
Fl. Angl. p. 448; Lightf. Fl. Scot. ii. p. 829; Engl. Bot. t. 1330. 
Cornicularia islandica Mudd Man. p. 77, t. 1, fig. 19 (1861). 
Exsice. Leight. n. 42; Mudd n. 51. 
A northern lichen, well known as Iceland Moss, and famed for 
its edible and medicinal qualities. The fronds vary in width from 
1-2 mm. to severalem. The marginal spines are usually occupied 
by spermogones, but sometimes they develop as haptera and anchor 
the plant to the surrounding vegetation. The white spots on the 
under surface are described by Wainio as pseudo-cyphellx. (Ark. 
Bot. viii. 4, p. 20 (1909) ). 
Hab. On the ground in heathy or stony places in upland or alpine 
situations.—Distr. Somewhat uncommon in the mountainous districts 
of the British Isles though plentiful among the Grampians, Scotland. 
—B.M. Wootton Common and King’s Lynn, Norfolk; near Sear- 
borough, Lowthorpe Moor, Stockton Forest, Langwith Moor and 
Stenshall Common, Yorkshire; Snowdon, Carnarvonshire; Pentland 
Hills near Edinburgh ; Ben Lomond, Stirlingshire; Ben More, Ben 
Lawers, Mael Graedha and Ben-y-Gloe, Blair Athole, Perthshire; Clova 
Mts. and Sidlaw Hills, Forfarshire; Ben-naboord, Lochnagar, Ben 
Macdhui, Morrone, Braemar and Countess Wells, Aberdeenshire. 
Form platyna Fr. Lich. Eur. p. 37 (1831).—Fronds broad, 
about 2 to 3 cm. wide, sparingly branched and less constantly 
spinulose at the margins. Apothecia large, about 1 cm. in 
diameter, submarginal, rather rare.—Leight. Lich. Fl. p. 96; 
ed. 3, p. 91 pro parte. C. islandica f. dilatata Norrl. in Medd. 
Sallsk. Faun. & FI. Fenn. i. p. 16 (1876) ; Cromb. in Journ. Linn. 
Soc. Bot. xvii. p. 575 (1880). Lichenoides rigidum, Eryngii folia 
referens Dill. Hist. Muse. p. 209, t. 28, fig. 111B (1741). 
Differs chiefly in the wider fronds ; there are numerous intermediate 
stages. 
Hab. On the ground among heaths in alpine places.—Distr. Con- 
fined to the higher Grampians.—B. M. Lochnagar, Ben-naboord, 
Cairngorm, and Cairntoul, Braemar, Aberdeenshire. 
Var. tenuifolia Wain. in Ark. Bot. viii. 4, p. 21 (1909).— 
Fronds cspitose, crowded, narrow, erect or depressed, the 
margins spinulose and connivent, the apices flattened out, white 
naked spots frequently present on the lower surface.—Cetraria 
