94 HERRE 



XX. Catillaria (Mass.) Th. Fr. 



Catillaria Massalongo, Ric. sul. Aut. Lich. Crost. 78. 1852. 

 Catillaria Th. Fries, Gen. Heterol. Europe. 88. 1861. 



Thallus crustaceous, uniform or marginally lobed, without cor- 

 tex. Apothecia circular, innate or sessile, with clear to black 

 proper margin but no thalline margin; disk concave to convex, 

 variously colored; hypothecium clear to black; paraphyses simple, 

 free or coherent, capitate; spores 8, rather small, colorless, ovoid 

 or ellipsoid, elongate or short, straight or curved, bilocular, with 

 thin walls and without a halo. 



A large genus, representatives occurring in all parts of the world 

 and upon all kinds of substrata. 



KEY TO THE SPECIES. 



A. On rocks. 



B. Thallus purplish black; apothecia black i. subnigrata 



BB. Thallus ash-colored; apothecia dark brown and blackening; 



white pruinose 2. franciscana 



A A. On bark. 



C. Thallus whitish ash-color or gray; becoming yellow with KOH 



3. tricolor 

 CC. Thallus greenish white; no reaction with KOH 4. globulosa 



i. CATILLARIA SUBNIGRATA (Nyl.) 



Lecidea subnigrata Nyl. Flora, 370. 1866. 



Lecidea subnigrata Leighton, Lich. Fl. Grt. Brit. ed. 3. 331. 1888. 



Thallus indeterminate, of purplish black squamules, imbricate, 

 lobed and crenulate, rugulose; KOH ; CaCl 2 O 2 . 



Apothecia sessile, .5 to i mm. wide; disk flat, black, finely papil- 

 late, at last markedly convex; margin at first thick but becoming 

 partly or wholly obsolete; hymenium 68 /* thick, pale purplish 

 gray, paling downward, blue with I; paraphyses subcoherent, the 



tips clavate; hypothecium colorless; spores ellipsoid, -= //, 



10 12 



On rocks near Stanford University, at an elevation of 500 feet. 

 A lichen of the British Isles. 



