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L. CONFERENDA (Nyl.) Eck. 
Thallus verruculose, granulate, obscurely cinerascent ; apothecia 
very small, black, convex and glaucous; spores oblong, simple, 
hyaline, ay mic. On rocks. 
BuEtuia De Not. 
B. capitulata Th. Fr. var. erudbescens (Flot.) Eck. 
Thallus of thin smooth flat discrete granules, becoming at 
length areolate; areoles irregular and evanescent at the outer mar- 
gin; apothecia scattered, more or less sessile, small and very 
black, flat and bordered by a well raised margin; spores ellipsoid, 
bilocular, fuscescent, oy mic. On smooth barks. 
B. punctiFrormis (Hoff.) Eck. 
Thallus very thin, scurfy, minutely granular, grey or whitish, 
becoming at length nearly obsolete or with a delicate coloration ; 
apothecia small, flat, granular and the disk quite rugose, brownish- 
black to very black, with a raised stout thick granular margin ; 
_ spores bilocular, +? mic. On smooth barks. 
B. albo-atra (Hoff.) Th. Fr. 
B. parasema (Ach.) Fr. 
B. disciformis Fr. 
B. spunia Schr. 
B. lepidastra Tuck. 
B. myriocarpa D. C. 
B. aTRATA (Sm.) Eck. 
Thallus blackish to ashy brown, areolate, broken, areoles plane, 
small, smooth, convex, hypothallus black; apothecia springing 
from the hypothallus, usually innate, small, appressed, margin thin, 
entire ; spores 8 in the thekes, bilocular,fuscous, 2-7 mic. On rocks. 
B. colludens Ny}. ne 
B. ExcENTRICA (Nyl.) Eck. 
Thallus brownish, white or gray, thin, sparingly more or less 
broken; apothecia pale, black, sessile, plane with a thickened ob- 
tuse margin. Spores we mic., the cells murilocular. 
B petraea (Flot.) Koerb. 
Var. grandis Fk. 
Var. Montagnei Tuck. (B. atro-alba Fr.) 
F. empetraca Nyl. 
