LECIDEA] LECIDEACEiE 85 



Lichen fuscoater L. Sp. PI. ed. 2, p. 1607 (1763); Lightf. Fl. 

 Scot. p. 804; With. Arr. ed. 3, iv. p. 11. L. fumosus Ach. 

 Lich. Suec. Prodr. p. 78 (1798). L. dcndritkus Dicks. Fasc. PI. 

 Crypt, iv. p. 21 (1801) ; Engl. Bot. t. 1734 (shows a well-marked 

 radiating hypothallus). L. cecliumenus Sm. Engl. Bot, t. 1830 

 (1808). Verrucaria fumosa HofFm. Deutschl. Fl. p. 190 (1795). 

 V. dendritica HofFm. I. c. p. 168. 



Exsicc. Leight. nos. 215, 216, 239, 306. 



Hah. On rocks. — Distr. Somewhat frequent in mountainous regions 

 of Wales, N.W. England, Scotland and W. Ireland. — B, M. Barmouth 

 and Cader Idris, Merioneth ; Malvern and near Droitwich, Worcester- 

 shire ; Long Mynd and Lyth Hill, Shropshire ; Langbaurghrigg, 

 Battersby and High Cliff, Cleveland, Yorkshire ; Barcaldine, Argyll ; 

 Ben Lawers, Perthshire ; Glen Callater, Braemar, Aberdeenshire ; 

 Glen Nevis, Invernessshire. 



Var. ^ grisella Nyl. Lich. Scand. p. 526 (1861).— Thalline 

 areolae contiguous, plane or somewhat convex, angulose, greyish 

 or whitish, opaque. Apothecia moderate, subinnate, plane or 

 slightly convex, black, often slightly pruinose, dark within, the 

 margin entire ; spores as in the type. — Lecidea gri sella Floerke 

 inFlot. Lich. Siles. (1829) nos. 141, 142; Cromb. Lich. Brit, 

 p. 83. L. fumosa var. y grisdla Floerke ex Schaer. Enum. p. 110 

 (1850) ; Mudd Man. p. 212. L. fuscoatra f. griseUa Leight. 

 Lich. Fl. p. 288 ; ed. 3, p. 294. L. interjecta Nyl. in Flora 

 xlix. p. 418 (1866) ; Cromb. Lich. Brit. p. 81 ; Leight. Lich. 

 Fl. p. 299 ; ed. 3, p. 306. Lichen diacapsis Sm. Engl. Bot. 

 t. 1954 (1809). 



Exsicc. Mudd n. 182 pro parte; Larb. Lich. Hb. n. 145. 



Readily distinguished from the type by the much paler, opaque 

 thallus. The numerous though usually somewhat scattered apothecia 

 are rarely somewhat different ; very rarely they are concentrically 

 arranged. 



Hah. On rocks and boulders, very rarely on brick walls, from 

 maritime to subalpine tracts. — Distr. Here and there in Great 

 Britain ; rare in W. Ireland ; not found with certainty in the Channel 

 Islands. — B. M. Near Hastings, Sussex ; Crown Hill, Devon ; near 

 Monmouth ; Dolgelly, Merioneth ; Lyth Hill, Shropshire ; Ayton 

 Moor, Cleveland, Langbaurghrigg, Yorkshire ; Durham ; near Hexham, 

 Northumberland ; Achosragan Hill, Appin, Argyll ; Ben Lawers, 

 Perthshire ; Letter Hill, Connemara, Galway. 



Form meiosporiza Leight. Lich. Fl. ed. 3, p. 294 (1879). — 

 Thallus whitish or greyish-white, rimoso-diffract. Apothecia 

 plane or subconvex, csesio-pruinose. — L. grisella f. meiosporiza 

 Nyl. in Flora lix. p. 239 (1876) ; Cromb. in Journ. Bot. xiv. 

 p. 362 (1876). 



Exsicc. Johns, n, 352. 



Differs merely in the constantly paler thallus and the pruinose 

 apothecia. As the name indicates, it has somewhat the aspect of 

 L. mciospora Nyl. but with pruinose apothecia. 



