450 LTCHEXACM. [lECAXOR.V. 



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 

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

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

 tine bluish, then wine-red with iodine. 



A very distinct species of which the type does not occur in this 

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

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



Form curvescens Xyl. Not. Siillsk. pro F. et Fl. Fenn. Fiirh. 

 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. 33. 



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. 



Hab. Encrusting mosses (Andreteas and Grimmias) 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 Snee, simple, colourless. Spermo- 

 gones with simple sterigmata and long straight spermatia. 



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

 Xyl. 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, internaU} blackish ; the thalline margin entire or subcrenu- 

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

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

 at the apices ; hvriienial gelatine bluish, with iodine. — Hook. Fl. 

 Scot. ii. p. 47 ; 8m. 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. — Riaodina atra Gray, Xat. 

 Arr. i. p. 449. Livhea 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. Lichenoides crustacetim et leprosinn, scutellis ni(jricantihvs 

 mojoribus et minorihus, Dill, in Ray, Syn. 71, 43 pro parte, Muse. 

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



Much resembles L. suhfusca var. cnilocarpa and L. f/aiujaJeoides, which 

 are frequently mixed up with it iu Ilerbaiia. From both of these, liow- 



