opegrapha] graphidace^ 235 



— B. M. Island of Sark ; near Ayton, Cleveland, Yorkshire; Cader 

 Idris, Barmouth and Llyn Gwernon, Merioneth ; Snowdon and Capel 

 Curig, Carnarvonshire ; West Water, Fifeshire ; Appin, Argyll ; 

 Mangerton and Diinkerron, Killarne^' ; Kilkee, Clare ; Lettermore, 

 Connemara, Galway. 



Form claresceus A. L. Sm. .Differs from the variety in the 

 more continuous greenish-white thallus and in the more regularly 

 scattered short apothecia. — 0. saxigena f. claresccns Nyl. in 

 Flora Ixii. p. 224 (1879) ; Cromb. in Grevillea viii. n. 30 (1879). 



Exsicc. Larb. Lich. Hb. n. 79. 



Hob. On rocks. — Distr. Rare in W. Scotland and W. Ireland. — • 

 B. M. Isle of Lismore, Argyll ; Twelve Pins and Kylemore, Connemara, 

 Galway. 



Var. Persoonii Stiz. torn. cit. p. 30, t. 2, f. 2, p and a. — 

 Thallus thin, whitish or greyish. Apothecia oblong, small, often 

 deformed; spores colourless, 3-septate, 0,021-23 mm. long^ 

 0,005-6 mm. thick.— Crom. Lich. Brit. p. 98 ; Leight. Lich. Fl. 

 p. 380 ; ed. 3, p. 403. Lichen Persoonii Ach. Lich. Suec. Prodr. 

 p. 19 (1798). 



Hab. On rocks. — Distr. Rare in N. Scotland and W. Ireland. — 

 B. M. Craig TuUoch, Perthshire ; Kilkee, Clare. 



Var. gyrocarpa Stiz. torn. cit. p. 29, t. 2, f. 2, e-o. — Thallus 

 greyish, limited and intersected by black lines. Apothecia 

 scattered, sessile, roundish, shortly ellipsoid or deformed, rarely 

 linear ; spores 0,020-25 mm. long, 0,004-6 mm. thick. — Cromb. 

 Z. c. ; Leight. //. c. 0. gyrocarjKi Flot. in Flora viii. p. 345 

 (1825). Verruca ria umhrosa Tayl. in Mackay Fl. Llib. ii. p. 97 

 (183G). 



Distinguished by the intersecting lines of the thallus and by the 

 usually deformed apothecia. Stizenberger {I. c.) states that the spores 

 are 2-celled or up to 7-celled. This condition has not been verified in 

 the British specimens. The spores are, however, difficult to find in 

 this variet3\ 



Hab. On rocks. — Distr. Rare in the Channel Islands, S. England, 

 N. Scotland and S. and W. Ireland. — B. M. Noirmont, Jersey ; 

 Luccombe, I. of Wight; Carig Mt., Kerry; Adragool, Kylemore, 

 Connemara, Galway. 



8. 0, atrula Nyl. in Flora Ix. p. 565 (1877).— Thallus very 

 scanty. Apothecia black, short, oblong, simple, prominent, 

 arranged in a somewhat parallel manner ; disc narrow ; spores 

 colourless, fusiform-oblong, 3-septate, about 0,016 mm. long, 

 0,0035 mm. thick. — Cromlx in Grevillea vi. p. 114; Leight. 

 Lich. Fl. ed. 3, p. 400. 



Exsicc. Larb. Lich. Hb. n. 39. 



The only specimens in the British IMuseum are imperfect and 

 without asci or spores ; the apothecia are small and rather thickly 

 scattered over the substratum. 



Hab. On mica-schist stones in shady places. — B. M. Kylemore, 

 Connemara, Galway (the only locality). 



