LECANOn.V.] LECANO-MOCIDKEI. 387 



Hah. Oil vpo-otiiblo detritus in maritime districts. — Distr. Only very 

 sparingly in y. En-rlaml and tlic S.^\■. Iliglilaiids of Scotland.— Ji. M. : 

 l.ucc-ondje Cove, Isle of \\'if,^lit j Koltiiigdeau Cliffs, Sussex. Aird.s, 

 Appin, Argylesliire. 



49. L. irrubata Nyl. ex Norrl. Mcdd. Siillsk. pro F. & Fl. Fcnn. 

 i. (187(5) p. 22. — Thallus determiii;ite, thin, rimose or rimoso- 

 areolato, sordid or f!,Tcyish (K — ). Apotheeia udiiate, small, hiato- 

 rine, somowhat plane or convex, immargiiiatc, yellow-reddish (K^- 

 purplish) ; spores ellipsoid or ovoid, simple, <),O0i)-(),(ll 1 mm. long, 

 0,0t)5-(; mm. thick. ; paraphyses scanty. — Cromb. Crovillca, xii. 

 p. 58. — Lecanora caJva var. irrubata Cromb. Lich. Brit. p. 47. 

 Lecklea irrubata Sm. Eng. FI. v. p, 1S3 ; Tayl. in Mack. Fl. llib. 

 ii. ]). 128. Lemnora ruj)estris forma viridi-Jlavescens (Wulf.) Leight. 

 Lich. Fl. p. 101, ed. 3, p. 204. Lecidea rupestris y. viridijlavescens 

 Mudd, Man. p. 104. Lichen riqn-stris Eng. liot. t. 2245. — Brit. 

 Kvs.: Leight. n. 119 ; Miidd, n. 161; Larb. Lich. Hb. n. 100. 



L^sually an-anged by authors among the Lecideei owing to its simple 

 spores and biatoriue api.thecia. Its true place, however, is among other 

 biatoriue species of tliis section, as shown by the siiermngones. From 

 the more developed thalhis, which is usually limited, it is to be regarded 

 as the specific type rather than the subspecies that follows. The apo- 

 thecia are numerous, usually small, rarely submoderate. The sjx'rmo- 

 gones, which are externally black-punctate, have the spermatia cylindrical, 

 about O,00o-G mm. long, 0,001 mm. thick. 



Ilab. On calcareous rocks, siliceous and cretaceous stones, and the 

 mortar of waUs in maritime and upland localities. — Distr. Not uncommon 

 in England ; not seen from \^'ales ; apparently rare in Scotland and 

 Ireland. — ]>. M. : Shiere, Surrey ; Beachy Head, Sussex; Anstey's Cove, 

 Torquay, and Cornworthy, S. Devon ; near Penzance, Cornwall ; Bath- 

 ampton Downs, Somersetshire ; Windsor Great Park, Berks ; Xorton, 

 near Worcester; Whitecliffe llncks, near Ludlow, Shropshire ; Bonsall, 

 Derbysliire ; Bilsdale and near Carlton, Cleveland, Yorkshire ; Beamish, 

 Durham ; Leven's Park, Westmoreland ; Chollerford, Northumberland. 

 Appin, Argyleshire ; Craig Tulloch, Blair Athole, Perthshire ; Kirkhmd, 

 Fifeshire. Killarney, co. Kerry ; Beu Bulben, co. Sligo ; near Kylemore, 

 CO. Galway. 



Subsp. L. calva Xyl. ex Lamy, Bnll. Soc. Bot. t. 3sx. (1883) 

 p. 379. — Thallus effuse, very thin, whitish, or scarcely any. Apo- 

 thecia small or moderate, convex, vitelline or tawny-j^ellow ; spores 

 0,009-0,014 mm. long, 0,005-8 mm. thick; paraphyses thick. — 

 Cromb, Grevillea, xviii. p. 46. — Lecanora calva Cromb. Lich. Brit. 

 p. 47. Lecanora rupestris form calva Leight. Lich. Fl. p. 191, ed. 3, 

 p. 203. Lichen calvus Dicks. Crypt, fasc. ii. (1790) p. 18, t. 6. f. 4 ; 

 With. Arr. ed. 3, iv. p. 14 ; Eng. Bot. t. 948. Lecidea. riq>estris 

 (?8cop.) Gray, Nat. Arr. i. p. 472; Sm. Eng. Fl. v. p. 183; Tayl. 

 in Mack. Fl. Hib. ii. p. 128 ; Mudd, Man. p. 193. 



Often spreads extensively with the thallus indistinct, being confused 

 with the substratum. The apothecia are at times somewhat large, and 

 then more convex, immarginate and scattered. 



