234 
THIRTEENTH REPORT. 
45. Pileus zonate, whitish with brownish zones, 2-4 mm. thick, later- 
ally much elongate, margin undulate and irregular; on Tsuga 
canadensis: Polyporus crispellus PK. 
(Tyromyces crispellus). 
45. Pileus not zonate, much thicker; pores glistening: (46) 
46. Pileus milk-white, very soft and fleshy, becoming fragile and rigid 
when dry ; tubes long, 5-10 mm. ; on conifers and other wood : 
Polyporus lacteus Fr. 
( Tyromyces lacteus ) . 
46. Pileus grayish-white to yellowish-white, watery with an acid odor; 
tubes short, 2-4 mm. long: Polyporus chioneus Fr. 
(Tyromyces chioneus). 
47. Pores whitish, then black-spotted; pileus and flesh reddisli-grav to 
clay color, dull red after wetting, with odor of seneca grass : 
Polyporus fra grans PK. 
( B j erkan dera puber u la). 
47. Pores and flesh whitish, yellow or orange; pileus velvety to finely 
tomentose: (48) 
47. Pores and flesh light brown to dark brown: (50) 
48. Pileus 2-3 cm. thick, orange colored, convex; flesh zonate, watery 
(fresh), rigid (dry) ; pores long, 5-10 mm. On oak, perhaps on 
other wood: Polyporus Pilotae Schw. 
(Aurantioporus Pilotae). 
48. Pileus thinner, 1 cm. or less thick, applanate, imbricate, often of 
many pilei : (49) 
49. Very imbricate, sulfur-yellow, fading to white, large, 7-20 cm. wide. 
On trunks of broad-leaved trees ; parasitic : 
Polyporus sulphurous Fr. 
(Laetiporus speciosus). 
49. Orange-colored, much smaller, 5-8 cm. wide; flesh spongy (moist), 
friable (dry) ; on wood of conifers : Polyporus fihrillosus PK. 
(Psychoporellus flbrillosus) . 
50. Parasitic on living stems of the currant bush; pileus ferruginous to 
umber, 5-10 cm. wide, conchate, tough and corky: 
Polyporus ribesius Pars. 
(P'yropolyporus Ribes). 
50. On wood of broad-leaved trees; pileus dimidiate, simple or somewhat 
imbricate: (51) 
51. Flesh distinctly zonate: (52) 
51. Flesh indistinctly or not at all zonate (54) 
52. Pores glistening; pileus medium size: (53) 
52. Pores dull, whitish when young, then resinous, dark brown; pileus 
of immense size, a foot or more wide; on oak: 
Polyporus dryadens Fr. 
( Innotus dryadens) . 
