450 LTCTENACEI. [LECANOEA.. 



mules) sublobulato-concrescent or sub-dispersed (K+ yellowish, 

 then blood-red, CaCl ). Apothecia moderate, plane, occasionally 

 slightly convex, brown or reddish-brown, the thalline margin 

 eiitire, at length excluded ; spores oblong or cylindrico-oblong, 

 simple, 0,021-27 mm. long, 0,006-7 mm. thick ; hyinenial gela- 

 tine bluish, then wine-red with iodine. 



A \-ery distinct species of wliicli the type does not occur in this 

 country, but only the following form, which seems to descend from var. 

 castanea (Hepp), Nyl., also unknown in Britain. 



Form curvescens Nyl. Not. Sallsk. pro F. et Fl. Fenn. Forh. 

 n. ser. v. (1866) p. 135 (nota). Thallus very thin, minutely gra- 

 nuloso-squamulose, dark reddish-brown. Apothecia with the 

 thalline margin often inflexed ; spores fusiform, at times spuriously 

 1-3-septate, occasionally somewhat curved, 0,030-34 mm. long, 

 0,005-6 mm. thick. Cromb. Lich. Brit. p. 53 ; Leight. Lich. Fl. 

 p. 214, ed. 3, p. 199. Pannaria curvescens Mudd, Man. (1861) 

 p. 125, t. 2. f. 38. 



The thallus is visible only here and there upon the substratum, from 

 which, when less developed, it is scarcely distinguishable. The apothecia 

 are but sparingly present, with the thalline margin at length obliterated. 



Hub. Encrusting mosses (Andreaeas and Grirnmias) in an alpine situa- 

 tion. Distr. Extremely local and rare on one of the S. Grampians, Scot- 

 land. B. M. : Summit of Ben Lawers, Perthshire. 



G. Apothecia lecanorine ; spores 8noe, simple, colourless. Spermo- 

 gones with simple sterigmata and long straight spermatia. 



144. L. atra Ach. Lich. Fniv. (1810) p. 334 (excl. vars. /3, y) ; 

 Nyl. Act. Soc. Linn. Bord. ser. 3, t. i. p. 336. Thallus determinate, 

 somewhat thick, granulate or verrucoso-unequal, whitish or greyish- 

 white (K + yellowish, CaCl ) ; hypothallus thin, blackish, limiting 

 the thallus. Apothecia moderate, sessile, plane or slightly convex, 

 black, internally blackish ; the thalline margin entire or subcrenu- 

 late, often flexuose; spores ellipsoid, 0,010-15 mm. long, 0,006-8 

 mm. thick ; paraphyses robust, not discrete, violet-coloured, darker 

 at the apices ; hymenial gelatine bluish with iodine. Hook. Fl. 

 Scot. ii. p. 47 : Sm. Eng. Fl. v. p. 186 ; Tayl. in Mack. Fl. Hib. ii. 

 p. 133 ; Mudd, Man. p. 145 pro parte ; Cromb. Lich. Brit. p. 54 ; 

 Leight. Lich. Fl. p. 194, ed. 3, p. 177. Rinodina atra Gray, Nat. 

 Arr. i. p. 449. Lichen ater, Huds. Fl. Angl. i. (1762) p. 445; 

 Lightf. Fl. Scot. ii. p. 813 ; With. Arr. ed. 3, iv. p. 18 ; Eng. Bot. 

 t. 949. Liclienoides crustaceum et leprosuin, scutellis nicjricantibus 

 majoribus et minoribus, Dill, in Ray, Syn. 71, 43 pro parte, Muse. 

 133, t. 18. f. 15 A.. Brit. Exs. : Larb. Lich. Hb. nos. 16, 54. 



Much resembles L. subfusca var. coilocarpa and L. ganyaleoidcs, which 

 are frequently mixed up with it in Herbaria. From both of these, how- 



