KEY TO THE ARRANGEMENT. 



11 



49. PLATYGRAPHA. Apothecia rounded, or oblong ; the 



proper exciple more or less obscure, bordered by an 

 accessory thalline or tballoid one. Spores fusiform, 

 quadri-plurilocular, colourless. Thallus uniform. 



50. MELASPILEA. Apothecia rounded, or oblong, black. 



Spores ovoid-ellipsoid, bilocular, brown, or decolorate. 

 Thallus uniform, or obsolete. 



Fam. 2. OPEGPAPHEI. Apothecia normally lirellseform. 



51. OPEGRAPHA. Apothecia lirellseform (very rarely 



rounded-difform), oftener simple, for the most part 

 superficial, the exciple almost always black through- 

 out. Spores smallish, from ellipsoid becoming finger- 

 shaped (dactyloid] or oftener fusiform, bi-quadri- 

 plurilocular, brown, or, much oftener, decolorate. 

 Thallus uniform, or almost obsolete. 



52. XYLOGRAPHA. Apothecia now angulate-patellseform, 



but oftener lirellseform ; the exciple softish, and origi- 

 nally pale, but at length black. Spores ellipsoid, 

 simple [or, at length, in a foreign species, somewhat 

 nmriform-pltirilocular] decolorate. 



53. GRAPHIS. Apothecia lirellaeform, oftener branched, 



or very rarely rounded-diflform, for the most part 

 innate ; the exciple either coloured, or black, but 

 more often colourless below, and bordered almost 

 always by an accessory thalline or thalloid one. Spores 

 ellipsoid, or oblong, quadri-plurilocular, or finally 

 muriform-multilocular, brown, or decolorate. Thal- 

 lus uniform, or now almost obsolete. 



Fam. 3. GLYPHIDEI. Many apothecia collected in a com- 

 mon, cushion-like thalloid receptacle (stroma). 



54. CHIODECTON. Apothecia rounded-difform, or oblong, 



plano-convex, immarginate, immersed in a white 



