342 LICHF.NACEI. "[rASNULARIA. 



Tavl. in Mack. Fl. Hib. ii. p. ]42. Lichen micrqpht/llns Eng. Bot. 

 t. 212S.—Bni. Exs. : Cromb. n. 153. 



Externally subsimilar to P. imcrojilvjlkt, but differs in the less iimi, 

 sq^uauiiilose thallus, and more especially in the infuscate hypotbecium. 

 It forms a thin or thinnish crust, with the squamules at first plane and 

 adnate on the bypothaUus, becoming at length granulose and ditfract, the 

 squamules being A'isible only at the immediate circumference. The 

 thallus varies somewhat in colour according to situation, becoming more 

 or less blackish, whence form nigricans Leigh t. Lich. Fl. ed. 3, p. 153. 

 The apothecia ai'e scattered and occasionally darker in colour, but ai*e 

 seldom present in om- specimens. 



Hub. On the trunks of old trees in wooded upland districts. —Disfr. 

 Somewhat local, though plentiful where it occurs in the mountainous 

 tracts of W. Britain and S.W. Ireland. — B. M. : Near Lydford, Hustyn's 

 AVood, and Lynton, Devonshire; St. Breock, Cornwall; Barmouth, Cwm 

 Bychan, and Harlech, Merionethshire ; Beddgelert, Carnarvonshire ; 

 Island of Anglesea. Isentmere, Westmoreland. Xew Galloway, Kirk- 

 cudbrightshire ; Inverary, Barcaldine, and Appin, Argyieshire ; Criaula- 

 rich, Loch Katrine, and Glen Lochay, Perthshire ; Craig Cluny, Braemar, 

 Aberdeenshire ; Glen Ach-na-Shilloch, Boss-shire. Glen Bower "Woods 

 and Glengariff, eo. Cork; Turk Mt. and Dinish, Killaruey, co. Kerry. 



Yar. /3. incrassata XyL c:c Lamy, Bull. Sec. Bot. t. xxv. (1878) 

 p. 3Sii. — Thallus thick, densely coraUoideo-stipate, brownish-black ; 

 hY|)othallus spougioso-rhizinose. Apothecia very rare, couvex, 

 brownish-black. — Cromb. Grevillea, xviii. p. 44. — Pannaria tn[jto- 

 jjhi/lki yar. incrassata Xyl. Xot. Sallsk. pro F. et Fl. F. Ftirh. y. 

 (1866) p. 124. Pannaria lasieUa Stirt. Scot. Nat. iy. p. 164. 



Distinguished by the darker, much thicker thallus (4-G mm. thick), and 

 by the peculiar hypothallus. It has only recently been met with in a 

 fertile condition. 



Hab. On the trunks of old ash trees, rardy on mossy ground among 

 roclis, in upland wooded districts. — Disfr. Local and scarce in the S.W. 

 Highlands, and among the S. andX. Grampians, Scotland. — B. M. : Glen 

 Creran, Barcaldine, Argyieshire (frt.) ; Glen Lochay, Killin, Perth- 

 shire. 



4. P. nigi-a Xyl. ex Stiz. St. Gall. Xat. Gcs. 18S2, p. 336.— 

 Thallus subdeterminate, minutely coralloidco-granuloso-crustaecous, 

 usually diffracto-areolate, thinnish, dark-greyish-black, brownish- 

 black or black ; hypothallus bluish-black. Apothecia lecideine, 

 small, plane or slightly convex, black, internally pale-whitish, the 

 margin entire, concolorous ; spores ellipsoid, 1-septate (or simple 

 and oleoso-locular), U, 011-18 mm. long, 0,UOo-7 mm. thick ; hypo- 

 thecium brownish-black, pnraphyses thick ; hymenial gelatine deep- 

 bluish and then dark-yiolet with iodine. — Cromb. Greyillea, xii. 

 p. .58. — Pannaria ni(jra Cromb. Lich. Brit. p. 43; Lcight. Lich, Fl. 

 p. 168, ed. 3, p. 154. Lecothecium nigrum Mass., Mudd, Man. p. 175 

 pro parte. CoUema nigrum Sm. ^ng. Fl. y. p. 207 ; Tayl. in Mack. 

 Fl. Hib. ii. p. 107. Placy ntluum nirfrum Gray, Xat. Arr. i. p. 395. 

 Lichen niffer Hud.s. Fl. Atigl. ii. (1 778) p. 524 ; With. Arr. iy. p. 10 ; 

 Eng. Bot," t. Mf^l.—Brit. Exs. : Lcight. n. 366. 



