OF GREAT BRITAIN. 393 



IV. LITHOGRAPHA, Nyl. 



Thallus crustaceous or evanescent ; apothecia lirellseform, black, 

 tumid, epithecium rimiform, margins thick, convex ; hypothecium 

 black, thick, entire ; spores 8 or numerous, simple or 1-septate. 



1. L. tesserata, (DC.) pale-brownish-grey, crustaceous, tessellato- 

 areolate, areolae plano-convex, (K yellow then red) ; apothecia 

 fuscous-black, lirellseform, slightly prominent, short, obtuse, simple 

 or slightly divided, solitary or clustered, straight or curved ; epithe- 

 cium rimceform, margin thick, inflexed ; hypothecium thick, black ; 

 spores 8, colourless, oblong or ellipsoid, simple, minute. 



On alpine rocks, rare. 



Syn -.—Opegrapha tesselata, DC. Fl. Fr. 2. 313. (1805.) Leight. Br. Graphid. 

 p. 8. Opegrapha petrcea, Ach. Syn. 72. IAthographa tesserata, Nyl. Scand. 290. 

 Mudd Man. 225. 



Fig :— B. Bot. Suppl. 2632. fig. 2. Leight. Br. Graph, t. 5. f. 1, 



Exs :— Leight. 396. Anzi Langob. 203. Th. M. Fries 46. Korb. 256. 



Geog. Distrib : — Sweden, Italy. 



Bot. Prov:— 1...7...10, 11, 12.. .15. 



England : — Holwiek Soar, on the Tees, Yorkshire. Mr. Robertson. Valley of 

 Rooks, Linton, N. Devon. Mr. Borrer. Middleton in Teesdale, Durham. Rev. 

 J. Harrriman. near Staveley. Mr. Martindale. 



Scotland : — Morrone ; Ben Lawers ; Cairn Gowar. Rev. J. M. Crombie. 



Wales : — Snowdon. Mr. Holmes. Cader Idris, north west side ! Llyn Aran ! 

 Llyn-y-Cae ! Cader Idris ; Aran Mowddy ! Cwm Cywion ! Glyder Vaoh ! Pass of 

 Llanberis ! Cwm Cwlyd ! Cwm Clyd ! Moel-y-gest ! near Tremadoe. 



"Spores .002 in. long, by .001 in. broad, t. 4. f. 87." (Mudd.) "Spores 

 .008—011 mm. long, .0045— .0065 mm. broad." (Nyl.) " Spores .010—15 mm. 

 long, .005—8 mm. broad." (T. M. Fr.) Spores .011 mm. long, .005 mm. 

 broad. 



2.' L. petrcea, (Durieu.) evanescent ; apothecia black, lirellseform 

 thick, linear, simple, somewhat shining, clustered and congregated, 

 fiexuose; epithecium rimaeform ; margin very thick, tumid, inflexed ; 

 hypothecium thick, black ; spores numerous, colourless, oblongo- 

 cylindrical, simple. 



On rocks, rare. 



Syn :— Mont. & Dur. Expl. Sc. Alger. 278. (1846.) Nyl. Prodr. 147. 



Exs : — Larbal. 40. 



Geoc. Distkib : — Algeria. 



Bot. Prov:— 26.. .31. 



Ireland : — Lettermore and near Kylemore ! Mr. Larbalestier. 



Channel Islands : — Le Fret Common ! Noirmont ! Jersey. Mr. Larba- 



" Spores .003—4 mm. long, .001 mm. broad.'' (Nyl.) 



3. L. dendrographa, Nyl. cinerascent, effuse or evanescent, 

 (K — C — ) ; apothecia black, linear or oblong or elliptical, simple or 

 slightly furcato-divided, erumpent ; epithecium black, opake, narrow, 

 at length applanate, margin prominent, thin, shining, more or less 

 fiexuose ; hypothecium fuscous-black ; spores numerous, colour- 

 less, ellipsoid, minute, simple ; paraphyses indistinct. 



On trees, rare. 1869. 



Syn :— Nyl. in Flora 1864. p. 488. Crombie Enum. 95. 



Geog. Distrib :— France. 



Bot. Prov :— 1, 2...31. 



England :— Near Totnes, S. Devon. Dr. Soil. (1869.) Budleigh Salterton. 

 Prof. Dickie. Kiver Dart ! Cornwall. Mr. Curnmc. Stoney Cross, New Forest. 

 WBtefield, Isle of Wight. Mr. Holmes. 



