180 LKCANO-LLIC'IDKKI | BUKLLIA 



p. 178; Tayl. in Mackay PI. Hib. ii. p. 122 ; Crumb. Lich. Brit, 

 p. 93 ; Leight. Lich. ¥1 p. 304 ; ed. 3, p. 316. 

 ExHicc. Larb. Lich. Hb. n. 14G. 



Has much the general aspect of more developed states of Dacidia 

 Jldvovirescens, of whicli it was subsequently regarded by Acharius as 

 a variety. Apart, however, from other characters, it differs in the 

 anatomical structure of the a[)othccia. In tlie IJritish specimens the 

 thallus usually forms small orbicular patclies. The apothccia are 

 numerous, often aggregate and confluent, arranged as it were in 

 circles. 



Hab. On the ground, rarely encrusting mosses on rocks in moun- 

 tainous districts, generally associated with Baiomyces rufus. — Distr. 

 Very local and scarce on the Grampians, Scotland, and in W. Ireland. 

 — B. M. Ben Lawers, Craig TuUoch, and Eannoch, Perthshire ; 

 Canlochan, Forfarshire ; Morrone, Braemar, Aberdeenshire ; near 

 Kyleinore, Connemara, Galway. 



Form athallina A. L. Sm, — Thallus absent; apothecia para- 

 sitic ; otherwise as in the type. — Lecidea scahrosa f. athallina 

 Nyl. ex Norrl. in Not. Siillsk. Faun. & Fl. Fenn. n. ser. x. p. 341 

 (1873). 



In one of the two British specimens there are traces of the proper 

 thallus, which probably is always normally present, though obliterated, 

 as in other instances, by the more vigorous growth of the host. 



Hab. On the thallus of Boiomyces rufus in mountainous regions. 

 — Distr. Bare on the Grampians, Scotland. — B. M. Ben Lawers, 

 Perthshire ; Braemar, Aberdeenshire. 



30. B. alpicola Krempelh. Lich.-Fl. Bay. p. 200 (1861).— 

 Thallus subdeterminate, thickish, areolate, the areolae rather 

 large, continuous or somewhat scattered, plane or slightly 

 convex, bright-yellow (K -|- deep yellow, at length orange-red, 

 CaCl — , medulla I — ); hypothallus black, distinct. Apothecia 

 black, appressed, plane and thinly margined, at length often 

 slightly convex, sessile, and immarginate ; hypothecium brownish- 

 black ; paraphyses concrete, black at the apices, spores ellipsoid, 

 greenish - black, 0,018-28 mm. long, 0,Q10-15 mm. thick; 

 hymenial gelatine deep-blue with iodine. — Lecidea alpicola 

 Nyl. in Act. Soc. Linn. Bord. ser. 3, i. p. 388 (1856) ; Cromb. in 

 Journ. Bot. viii. p. 99 (1870) & in Grevillea iii. p. 143; 

 Leight. Lich. Fl. p. 315 ; ed. 3, p. 328. L. geograpJilca var. 

 alpicola Schser. Spicil. p. 124 (1828) & Enum. p. 106. L. airo- 

 virens var. alpicola Wahlenb. Fl. Lapp. p. 474 (1812) pro parte. 



Externally subsimilar to states of Bhizocarpon geographicttm, 

 with which, at first sight, it might readily be confounded. It differs, 

 in the rather larger areolae and apothecia, and more especially in the 

 1 -septate shorter spores and the thalline reaction with hydrate of 

 potash. x\pparently one of our rarer British lichens. 



Hab. On quartzose and v/hinstone rocks and boulders in alpine 



