LECANORA. ] LECANO-LECIDEEI. 373 
Hab. On schistose walls if a maritime district—Distr. Only very 
sparingly in N.E. Scotland; no doubt to be detected elsewhere.—B. M.: 
Portlethen, Kincardineshire. 
30, L. aurantiaca Nyl. Mém. Soc. Cherb. t. v. (1858) p. 112; 
Lich. Scand. p. 142.—Thallus determinate or subeffuse, thinnish, 
granulato-verrucose, unequal, yellowish or pale-lemon-coloured (K+ 
purplish) ; hypothallus dark-greyish, limiting the thallus, often 
obsolete. Apothecia moderate, sessile, plane or somewhat convex, 
orange-coloured (K+ deep violet), usually biatorine with entire 
proper margin; the thalline margin thin, crenulate, speedily ex- 
cluded ; spores ellipsoid, polari-bilocular, 0,012-18 mm. long, 0,007 
-10 mm. thick.—Cromb. Lich. Brit. p. 46.—-Lecanora aurantiaca 
var. salicina Leight. Lich. Fl. p. 217, ed. 3, p. 206. Callopisma 
aurantiacum a. salicinum Mudd, Man. p. 186. Lecidea aurantiaca 
Sm. Eng. Fl. v. p. 186; Tayl. in Mack. Fl. Hib. ii. p. 129; Gray, 
Nat. Arr. i. p. 476. Lichen aurantiacus Lightf. Fl. Scot. ii. (1777) 
p- 810 pro parte. Rinodina salicina Gray, Nat. Arr. i. p. 456, 
Lichen salicnus Eng. Bot. t. 1305. Lichen fl worubescens Huds. FI. 
Angl. p. 443 pro parte; With. Arr. ed. 3, iv. p. 15 pro parte.—— 
I have retained Lightfoot’s specific name, instead of the more deter- 
minate one LZ. salicina Ach., owing to its being generally accepted, 
though it includes also the subspecies that follows.— Brit. Exs.: 
Mudd, n. 99; Leight. n. 212; Bohl. n. 118. 
A very distinct species which cannot be confounded with any of its 
allies. The thallus is somewhat variable in colour, being occasionally 
whitish or greyish (when the reaction is less distinct), and at times is 
almost evanescent. The apothecia are numerous, though chiefly central, 
and except in a very young state are biatoroid. In otherwise sterile 
plants the spermogones are especially frequent and papilleform, with 
spermatia 0,003-4 mm. long, scarcely 0,001 mm. tlick. This state is 
described by Acharius (Vet. Ak. Handl. 1810, p. 148) as var. microthelia 
(cfr. Gray, Nat. Arr. i. p. 456). 
Hab. On the trunks of trees, chietly poplars, ash, and willows, also on 
old pales, in maritime, lowland, and upland situations.—Distr. General 
and common in England, probably also in Wales, Scotland, and Ireland ; 
yare in the Channel Islands.—B. M.: Island of Guernsey. Hadiscoe, 
Suffolk; Walthamstow, Essex; Halstead, Kent; Sussex; near St. 
Helen’s and Bembridge, Isle of Wight; Isham Valley, Torquay, and 
near Plymouth, 8. Devon; Cornwall; Windsor Great Park, Berkshire ; 
Malvern and near Crowle, Worcestershire; Gopsall Park, Leicestershire ; 
Oswestry and Shrewsbury, Shropshire; Black Mount, Abergavenny, 
Monmouthshire; Garn, Denbighshire; Island of Anglesea; Teesdale, 
Durham; Hexham and Wansbeck, Northumberland; Levens, West- 
moreland, New Galloway, Kirkcudbrightshire ; Largs, Ayrshire; near 
Edinburgh; Connel Ferry, Argyleshire; Finlarig, Killin, Perthshire ; 
Abergeldie, Braemar, Aberdeenshire. Near Belfast, co. Antrim; Clon- 
mel, co. Tipperary ; Ballynegard, co. Limerick. 
Subsp. 1. L. erythrella Nyl. Flora, 1873, p. 549.—Thallus 
effuse, thin, or submoderate, areolato-diffract, or rugose and rimose, 
yellow or orange-yellow (K+ crimson). Apothecia biatorine (rarely 
