LECANORA.] LECANO-LECIDEEI. 373 



Hob. On schistose walls in a maritime district. Distr. Only very 

 sparingly in N.E. Scotland ; no doubt to be detected elsewhere. B. M. : 

 Portlethen, Kiucardineshire. 



30. L. aurantiaca Kyi. Mem. Soc. Cherb. t. v. (1858) p. 112 ; 

 Lich. Scand. p. 142. Thallus determiiiate 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 (K4- deep violet), usually hiatorine 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. 136. 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. 

 Lich">i saJicinus Eng. Bot. t. 1305. Lichen ft ivombescens Huds. Fl. 

 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 L. salicina Ach., owing to its being generally accepted, 

 though it includes also the subspecies that follows. Brit. Exs.: 

 Mudd, n. 09 ; 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 papillaBibrm, with 

 spermatia 0,003-4 mm. long, scarcely 0,001 mm. tl ick. This state is 

 described by Acharius (Vtt. Ak. Handl. 1810, p. 148) as var. microthelia 

 (cfr. Gray, Nat. Arr. i. p. 456). 



Hub. On the trunks of trees, chiefly poplars, ash, and willows, also on 

 old pales, in maritime, lowland, and upland situations. Distr. General 

 and common in England, probablv also in Wales, Scotland, and Ireland ; 

 rare 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 ; Ilsham Valley, Torquay, and 

 near Plymouth, S. 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-f- crimson). Apothecia biatorine (rarely 



