LECANORA.j LECANO-LECIBEEI. 455 



ii. p. 49; Sm. Eng. Fl. v. p. 190; Tayl. in Mack. Fl. Hib. ii. 

 p. 136 ; Cromb. Lich. Brit. p. 57 ; Leight. Lich. Fl. p. 232, ed. 3, 

 p. 224. Hinodina hcematomma et R. porphyria Gray, Nat. Arr. 

 i. p. 457. As the specimens published by Dickson are suffi- 

 ciently typical, his specific name has priority. Brit. Exs. : Dicks. 

 Hort. Sic. n. 24 ; Leight. n. 214 ; Mudd, n. 130 ; Larb. Lich. Hb. 

 n. 339 ; Bohl. n. 120. 



The thallus spreads very extensively and varies somewhat in thickness 

 and colour. In some other countries it occurs on the trunks of aged 

 trees, hut it has not with certainty been found upon such in Great 

 Britain ; though what may he the sterile thallus has been noticed spar- 

 ingly on oaks in the New 'Forest. The apothecia are numerous, though 

 somewhat scattered, with the thalline margin often obliterated. The 

 spermogones, which are very minute, scattered, and slightly prominent, 

 might readily be mistaken for very young apothecia, with which they are 

 concolorous. 



Hab. On shaded perpendicular rocks and boulders in maritime and 

 upland districts. Distr. Probably general and common in Britain and 

 the Channel Islands, as also in Ireland ; but from the nature of the 

 habitat specimens are with difficulty obtained. B. M. : llozel, Island of 

 Jersey; Islands of Guernsey, Brechou, and Alderney. Withyam and 

 Ardingley, Sussex ; near Penzance, Cornwall ; Stonehenge, Wiltshire ; 

 Acton Burnell and Nesscliff Hill, Shropshire ; Moel-y-golfa, Montgo- 

 meryshire ; Barmouth, Merionethshire ; Nant Francon, Carnarvonshire ; 

 Battersby, Cleveland, Yorkshire; near Eglestone, Durham; Harlaw 

 Hill, Northumberland. Roslin, near Edinburgh ; Bowling Bay, Dumbar- 

 tonshire ; Airds, Appin, Argyleshire ; West W'ater, Fife ; The Trossachs 

 and Craig Calliach, Perthshire ; Portlethen, Kincardineshire ; Morroue, 

 Braemar, Aberdeenshire ; Glen Nevis, Inverness-shire. Near Belfast, 

 co. Antrim ; Western Blasquet Island, co. Kerry. 



Yar. /3. saxetana Cromb. Grevillea, xviii. (1890) p. 70. Thallus 

 subcontinuous, thickish, white or whitish. Apothecia sessile, con- 

 vex, dark sanguineous ; the thalline margin obliterated. Lecanora 

 Jicematomma form, saxetana Cromb. Lich. Brit. p. 58. Lecidea 

 saxetana Ach. Vet. Ak. Handl. 1808, p. 269. 



Distinguished by the less pulverulent, constantly whitish thallus and 

 by the darker biatoroid apothecia. It seems a distinct variety rather than 

 a state of the so-called variety porphyria (Pers.), into which the type 

 passes in certain situations. 



Hab. On the side of an exposed perpendicular rock in an upland dis- 

 trict. Distr. Only very sparingly on one of the N. Grampians, Scotland. 

 B. M. : Morrone, Braemar, Aberdeenshire. 



151. L. elatina Ach. Lich. Univ. (1810) p. 387. Thallus effuse, 

 thin, granulato-leprose, whitish or pale-yellowish (K + yellow, 

 CaCl ). Apothecia moderate, sessile, brownish-testaceous (K ), 

 at first somewhat plane wit"h thin entire thalline margin, then 

 convex and biatorine ; spores fusiformi-acicular, 3-5-septate, usually 



