102 NORTH AMERICAN FLORA 
Context fulvous, opaque. 
Spores hyaline ; tubes thick-walled. . 
Pileus simple, sulcate, sometimes polished, margin usu- 
ally narrow and rounded; not found on species of 
Prunus. 
Pileus terraced, imbricate or semi-resupinate, rarely sul- 
cate, never polished, margin broad, making an obtuse 
angle ; found on species of Prunus. 
Spores yellowish-brown ; tubes thin-walled. 
Context melleous, lustrous. 
Pileus small, 5cm. broad; found on /untperus. 
Pileus large, 8 cm. or more broad; found on Bezula. 
Surface remaining brown, with crust entire; species tropical. 
Hymenium roseocinereous to smoky-gray. 
Hymenium ferruginous to fulvous. 
Context ferruginous; surface dark-brown, marked with nar- 
a 
Nn UF Wh 
tow black concentric lines; tubes thin-walled, 5toamm. 7. 
Context tawny ; surface black, without lines and more sul- 
cate ; tubes smaller, thick-walled, 7 to a mm. 8. 
Surface black or nearly so and soon becoming very rimose; spe- 
cies all brown-spored. . 
Species confined to temperate regions. 
Tubes short, 1-5 mm. long each season; found abundantly 
on Robinia. 9. 
Tubes long, over 5mm. long each season; found rarely and 
only on Quercus. 10. 
. BP. Cedrelae. 
Species confined to the tropics. 
Pileus very large, 12 cm. or more broad, margin rounded. 11 
Pileus scarcely attaining 12 cm. in width, margin angular. 
Tubes large for the genus, 3-4 to a mm., thin-walled; 
spores 7 X 9u, cystidia none. 12. 
Tubes 5-7 to a mm., thick-walled. 
Pileus applanate, dimidiate, of light weight and soft- 
woody texture. 
Pileusungulate, conical, pendulous, vertically attached, 
of heavy weight and stony texture. 
Context reddish-fulvous to latericeous; species very rare, found only on 
Juniperus. 
Older pores visible in projecting annual layers; tubes 3-4 to a mm., 
thin-walled; pileus deeply furrowed, not rimose. 
Older pores not externally visible ; tubes 1-2 toa mm., thicker-walled ; 
surface very rimose. 
Pileus thin or of moderate thickness, conchate to applanate, never truly 
ungulate, 
Context ferruginous to fulvous. 
Surface soon covered with a thick, glabrous, horny, dark crust. 
Tube-layers very prominent, tubes stuffed with white mycelium. 
Tube-layers. distinct but not: prominent, tubes not conspicuously 
stuffed. 
Dissepiments thick ; hymenium concolorous with the context ; 
surface not rimose with age. 
Dissepiments thin; hymenium at length darker than the con- 
text; surface rimose in age. 
Surface anoderm or slightly encrusted. 
Hymenium chestnut-brown, glistening ; tubes 3-5 mm. long each 
17. 
15, 
16. P. Earlei. 
[VoLUME 9 
. PB igniarius. 
. P. fulvus. 
. BP. Everhartii. 
. PP. texanus. 
. P. Bakeri. 
. P. roseocinereus. 
P. inflexibtlis. 
P. Calkinsit, 
P. Robiniae. 
P. praerimosus. 
P. Underwoodit, 
13. P. yucatanensis. 
14. P. dependens. 
P. juniperinus. 
P. grenadensis. 
18. P. pseudosenex. 
9. P. jamiaicensis. 
season ; pileus large, velvety, ferruginous to fulvous. 20. P. Robinsoniae. 
Hymenium isabelline to fulvous. _ 
Pileus broadly effused, slightly reflexed, often wholly resupinate; 
spores globose, hyaline, 4-5, ; cystidia present. 21. P. conchatus. 
Pileus turbinate-conical, attached at the vertex ; spores ovoid, 
hyaline, 6-7 ~ 4-54; cystidia none. 22. P. Baccharidis. 
Pileus dimidiate to flabelliform, normally attached. 
Surface conspicuously tomentose, soft to the touch ; tubes 
short, fulvous within. 
Tubes 5-6 to a mm. 
Context punky, opaque ; found on species of Rives in 
temiperate regions. 
Context corky to woody, with a silky luster ; found on 
trunks of trees in Mexico and Central America. 
Tubes very minute, 8-10 to a mm. 
Pileus 4-8 cm. broad, concave below, surface remaining 
conspicuously tomentose. 
Pileus 10-25 cm. broad, plane below, surface becoming 
quite glabrous. 26. 
Surface soon encrusted, hard ; tubes avellaneous within, 46 
mim. long each season. 27. 
Context flavous to luteous. 
Surface conspicuously fibrose-lacerate. 28. 
Surface inconspicuously tomentose or glabrous. 
24, 
25. 
Ribis. 
linteus. 
Subpectinatus, 
Langloisit, 
calcttratus. 
uw & hy 
. Sarcitus, 
