36 
Section 2, BIATORA T. Fries. 
Substratum rock or earth. 
Thallus not squamulose or only indistinctly so. 
Pulverulent, light gray to sordid white, or obsolete. 29. 
Furfuraceous to indistinctly squamulose......... 32. 
Thallus squamulose. 
Squamules small, not imbricate..... 
Squamules larger, 
Peripheral squamules radiate. .............. 33. 
Peripheral squamules not radiating. ........ 22. 
Substratum bark, 
Thallus uniformly granulose, not becoming verrucu- 
lose, 
Light yellowish greenish........................ 24, 
Dusky greenish gray...........00.0 2 0c cee cece 26, 
Thallus granulose to verruculose. 
Thallus when present of some,shade of brown. 
Of an ordinary brown..........2..........-. 34, 
Dull brown or deficient..................... 30. 
Thallus not brown, 
Sordid white; apothecia brown black... .... 31. 
Not white, gray of some shade, 
Apothecia brown. 
Light brown, flattened, grouped..... 23. 
Rusty brown, not flattened.......... 27. 
Apothecia blackening. 
Dark brown to dull black. . . 
Section 3. PSORA (Hall.) T. Fries. 
Substratum wood or bark; thallus squamulose, the squam- 
ules dusty brown or deficient. ..................00006 38. 
Substratum mineral. 
Substratum rock. 
Squamules large, cervine brown, polished. ...... 41. 
Squamules small. 
Dark brown to black...............2...2.2... 42. 
Red brown...........0....2 cece cece ee eee eee 43, 
Substratum earth. 
Squamye pink red...........0 020000 e eee eee 40. 
Net pink, red brown to brown. 
Apothecia minute, central on squame....... 37. 
Apothecia large. 
Situated near border of squame........ 39. 
Not near border of squame, central. 
Apothecia globular..........2...... 36. 
Apothecia not globular, flat..... 2... 44, 
1. Lecidea atrobrunnea (Ramond) Schaer. 
eeeeeeeeeeee. 3D, 
CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
L.. phaeophora, 
L. coarctata, 
L. subplebeia. 
L. granulosa phylli- 
zans. 
L. glebulosa. 
LL. quernea. 
L. viridescens. 
LL. xanthococcoides. 
L. myriocarpoides. 
L, turgidula. 
L. varians. 
LL. vernalis. 
L. fuscescens, 
L. flecuosa. 
L, friesti, 
L, rubiformis. 
L. rufonigra. 
LL. scotopholis. 
LL. crenata. 
L. luridella. 
I. decipiens. 
L. globifera, 
L. lurida, 
Thallus determinate, chestnut brown to darker, squamulose-areolate; squamules 
in our species mostly approximate or contiguous, lobulate or flexuous and concave 
to undulate and convex, glistening, the border blackening; apothecia sessile, the 
