»7 



tia fistulous, cup or funnel-shaped, (Scyphiferse,) or much branched, 

 or rarely club-shaped ; horizontal thallus squaraulose, crustaceous, 

 or obsolete. A large genus of earth Lichens. 31 spp. and 5 suhspp. 



Genus 43. Thamnolia. Apoth. subglobose-patellseform ; many 

 together immersed in cephalodium-like thalline receptacles opening 

 by cribrose perforations ; not black. Spores simple, colorless. Po- 

 detia cylindrical, subulate, fistulous ; horizontal th. deficient; A 

 genus of a single Alpine and Arctic sp., with us sterile. 



Fam. 2. Coenogonii. Thallus horizontal, conferva-like. 



Genus 44. Coenogootum. Apoth. patellseform. Spores simple 

 or 2 loc, colorless. Th. of jointed filaments, densely intertangled. 

 A small tropical genus. 3 or 4 spp. 



Genus 45. Cystocoleus. A sterile, confervoid, dark-colored 

 plant, erectish, the cells surrounding the central one coalescing into 

 a sheath. Fruit unknown. The single sp. occurs on the Atlantic 

 coast. 



Fam. 3. Lecideei. Thallus crustaceous, now lobulate, or rarely 

 caulescent, mostly uniform ; adnate. 



Subf am. 1 . B.«;omtcei. Apoth. prolonged downward into a stipe. 



Genus 46. B^omyces Fie. Apoth. patellaef6rm or cephaloid, 

 the stipe now disappearing. Spores simple or 2-4 locular, colorless. 

 Th. horizontal, lobulate or uniform. A small genus of earth lichens. 



Subfam. 2. Biatokei. Apoth. sessile, the exciple paler than the 

 disk. 



Genus 47. Biatoea, Fr. Apoth. patellseform or oftener cepha- 

 loid, (now blackening, but not carbonaceous); spores . simple, or 

 from fusiform becoming acicular, and 2-4-plurilocular, colorless. 

 Th. now lobulate ; mostly uniform. A very large genus. The 

 forms with squamose thallus constitute the § Psora ; those with uni- 

 form th. and simple spores § Eubiatora ; with two locular spores § 

 Biatorina*; witli fusiform 4-plurilocular spores § Bilimbia ; with 

 acicular spores § Bacidia ; and with very numerous spores in the 

 thekes § Biatorella. Many of our spp. remain to be determined. 



Genus 48. Heteeothecium (F1.) Tuck. Apoth. patellseform, 

 the exciple often thickened and lecanoroid. Spores simple, or 2- 

 plurilocular, or muriform, brown or decolorate. Th. uniform. A 

 rather small, and mostly tropical genus, which here includes Lopa- 

 ium, Megalospora, Bombyliospora, &c., of authors. 



Subfam. 3. Eulecideei. Apoth. sessile ; exciple- coal-black. 



