buellia] lecideace^ 171 



tips ; spores oblong or oblong-ellipsoid, pale-greenish-brown, 

 small, 0,006-10 mm. long, 0,002-4 mm. thick. — B. nigrihila 

 Mudd Man. p. 217 (1861). Lecidea nigritula Nyl. in Bot. Not. 

 1853, p. 99 ; Cromb. Lich. Brit. p. 89 ; Leight. Lich. Fl. p. 307 ; 

 ed. 3, p. 321. 



Closely resembling some forms of the preceding, but differing in 

 the small size and paler colour of the spores. 



Hab. On trunks of trees and on wood. — Distr. Rare in S., Central 

 and N. England.— i?. M. New Forest, Hants ; Trefriw, Carnarvon- 

 shire ; Farndale, Yorkshire ; Levens Park, Kendal, Westmoreland. 



12. B. prsecavenda A. L. Sm. — Thallus effuse, very thin, 

 blackish-green, scarcely visible (K — , CaCl — ). Apothecia 

 subminute, plane or slightly concave, thinly margined, reddish- 

 brown or black ; paraphyses slender, conglutinate, dark-amber- 

 brown at the tips, forming a reddish-brown epithecium ; 

 hypothecium (especially above) reddish-brown ; spores ellipsoid, 

 reddish-brown, 0,014-17 mm. long, 0,006-8 mm. thick ; hymenial 

 gelatine bluish then wine-red with iodine. — Lecidea prsecavenda 

 Nyl. in Flora Hi. p. 411 (1869) ; Cromb. in Journ. Bot. vii. p. 232 

 (1869) & Lich. Brit. p. 88 ; Leight. Lich. Fl. p. 309 ; ed. 3, p. 323. 



Distinguished by the biatorine character of the apothecia and bj' 

 the reddish colour internall3^ In the single specimen gathered the 

 thallus and apothecia are sparingly present, and are interspersed 

 with a sphaeriaceous fungus. 



Hah. On a decaying holly. — B. M. Near Lyndhurst, New Forest, 

 Hants. 



13. B. aBthalea Th. Fr. Lich. Scand. p. 604 (1874).— Thallus 

 effuse, thin or thickish, minutely cracked-areolate, greyish or 

 brownish-grey (K + yellow then red, CaCl — ) ; hypothallus 

 black. Apothecia minute, innate, concave or almost plane, with 

 a thin prominent margin ; hypothecium brownish or dark-brown ; 

 paraphyses coherent, dark-brown at the apices ; spores ellipsoid, 

 usually constricted at the septum, dark-brown. 0,010-15 mm. 

 long, 0,006-8 mm. thick ; hymenial gelatine deep blue with 

 iodine. — J5. hadioatra var. atroalhella Mudd Man. p. 214 

 (1861). Gyalecta sethaJea Ach. Lich. Univ. p. 669 (1810). 

 Lecidea atroalba var. atroalhella Nyl. Obs. Syn. Lich. Holm. p. 6 

 (1853). L. atroalhella Leight. Lich. Fl. p. 310 (1871); ed. 3, 

 p. 324. L. sethalea Stiz. in Jahresber. St. Gall. Nat. Ges. 

 p. 456 (1882); Cromb. in Journ. Bot. xx. p. 275 (1882). 



Exsicc. Mudd n. 185 (as B. coracina) ; Leight. n. 184 (as 

 Lecidea atroalba var. atroalhella). 



The thallus is typically very thin, the areolas being contiguous or 

 dispersed on a black hypothallus ; when more developed the areolae are 

 more compact and deeply cracked. 



Hah. On quartzose and schistose rocks. — Distr. Rather rare in 

 maritime and upland districts. — B. M. Lyth Hill and near Church 



