PERTUSARIA. | LECANO-LECIDEEI. 497 
pulverulent, in convex, thinly margined, at length immarginate 
verruce (K-+yellow, K(CaCl)+violet) ; spores 0,190-236 mm. 
long, 0,050-070 mm. thick.—Cromb. Grevillea, xix. p. 59.—Vario- 
laria amara Ach. Lich. Univ. (1810) p. 824; Hook. Fl. Scot. ii. 
p- 46; Gray, Nat. Arr. i. p. 491. Lichen fagineuvs Linn. Huds. FI. 
Angl. p. 443 ?; Lightf. Fl. Scot. ii. p. 807 ?; With. Arr. ed. 3, iv. p. 4 
pro parte; Eng. Bot. t. 1718. Variolaria faginea Turn. & Borr. 
Lich. Br. p. 64; Sm. Eng. Fl. v. p. 169 (non Tayl. in Mack. Fl. 
Hib. ii. p. 112). Pertusaria faginea Leight, Lich. Fl. p. 242, ed. 3, 
p- 232. Lichenoides candidum et farinaceum, scutellis fere planis 
Dill. Muse. 131, t. xviii. f. 11 C.—As Lichen fagineus of the older 
authors is for the greater part a “nomen vagum,” the determinate 
and very expressive trivial name of Acharius is here adopted.— 
Brit. Exs.: Mudd, n. 263 pro parte. 
As noticed by Acharius (/. ¢.) the taste of the whole lichen is very 
bitter, almost as in Cinchona. It has at times been confounded with the 
discoid state of P. globulifera, but the taste, the chemical reactions, and 
the smaller verrucz keep it distinct. The soredia are very numerous, 
confluent, frequently almost obliterating the thallus except towards the 
circumference. In Britain, as elsewhere, the apothecia are very rare in a 
well-developed condition. 
Hab. On trunks of old trees, chiefly beech and elms, occasionally ash, 
jn maritime and upland wooded tracts—Dvstr. General and not un- 
common in Britain; apparently rare in 8.W. Ireland; not seen from the 
Channel Islands.—B. M.: Great Glenham, Suffolk; Hainault Forest and 
near Gosfield, Essex ; St. Leonard’s Forest, Sussex; New Forest, Hants; 
Lydford, 8. Devon; Withiel and near Penzance, Cornwall; Minsty, 
Wiltshire; Cwm Bychan, Merionethshire; Island of Anglesea; Teesdale, 
Durham; Windermere, Westmoreland; Asby, Cumberland; Meldon 
Park, Northumberland. Near Glasgow, Lanarkshire; Craigforth, Stir- 
ling; Airds, Appin, Argyleshire; Finlarig, Killin, Perthshire ; Craig 
Cluny, Braemar, Aberdeenshire; Applecross, Ross-shire. Dunkerron, 
co. Kerry. 
10. P. velata Nyl. Lich. Scand. (1861) p. 179.—Thallus deter- 
minate, smoothish or rugoso-unequal, rimulose, obsoletely radiato- 
rugose or plicate towards the circumference, whitish or milk-white 
(K—, CaCl+red). Apothecia submoderate, plane, lecanoroid, pale 
or white-suffused, thinly veiled, in small, depressed, concolorous 
yerruce ; spores very large, 0,214-310 mm. long, 0,067-090 mm. 
thick, or occasionally somewhat smaller—Mudd, Man. p. 274; 
Cromb. Lich. Brit. p. 59; Leight. Lich. Fl. p. 241, et ed. 3, p. 232 
pro parte.— Variolaria velata Gray, Nat. Arr. i. p. 490; Sm. Eng. 
Fl. v. p. 170.—Parmelia velata Turn. Trans. Linn, Soc. ix. (1808) 
p- 143, t. 12. f.1. Lichen velatus Eng. Bot. t. 2062. 
Might readily be taken fora state of Lecanora parella, but is at once 
distinguished by the veiled apothecia and the thalline reaction with CaCl 
From Pertusaria multipuncta, which it more distantly resembles, it 
similarly differs in the reaction, as also in the form of the apothecia and 
the larger spores, The fertile verruce are occasionally very numerous 
and crowded. 
2k 
