24 WESTERN POLYPORES 



tubes 1-1.5 mm - long, isabelline to umbrinous, mouths angular, 

 yellow with a tinge of cinnamon, 3 to a mm., edges thick, be- 

 coming thin, entire; spores oblong, hyaline or pale-flesh-colored, 

 11-13 X 4-5 /* 



Frequent throughout on dead coniferous trunks. It occurs 

 also in Japan. 



20. FOMES Gill. 



Hymenophore sessile, ungulate or applanate, epixylous; 

 surface anoderm or encrusted, sulcate, rarely zonate; context 

 white, wood-colored, or flesh-colored, corky or woody, rarely 

 punky; tubes cylindric, usually thick- walled, stratose; spores 

 smooth, hyaline or subhyaline. 



Context rosy, light-brown in faded specimens. i. F. roseus. 



Context white or nearly so. 



Pileus encrusted; surface darker than the context. 



Pileus thin, distinctly zonate. 2. F. annosus. 



Pileus thick, ungulate, sulcate. 3. F. ungulatus. 



Pileus not encrusted; surface concolorous with the context. 



Tubes 3-4 to a mm.; pileus cylindric at maturity. 4. F. Laricis. 



Tubes 1-3 to a mm.; pileus ungulate at maturity. 5. F. amarus. 



i. FOMES ROSEUS (Alb. & Schw.) Cooke 



Pileus woody, dimidiate, varying from conchate to ungulate, 

 often imbricate and longitudinally effused, 2-4 X 6-30 X 0.5-3 

 cm.; surface rugose, subfasciate, slightly sulcate, rosy or flesh- 

 colored, becoming gray or black with age; margin acute, becoming 

 obtuse, sterile, pallid, often undulate; context floccose-fibrous to 

 corky, rose-colored, 0.2-2 cm. thick; tubes indistinctly stratose, 

 1-2 mm. long each season, mouths circular, 3-4 to a mm., edges 

 obtuse, concolorous; spores ellipsoid, smooth, thick-walled, 

 subhyaline, 3.5 X 6 p. 



Common throughout on living or dead trunks of conifers, 

 causing a serious rot. The variation in the form of the hymeno- 

 phore from conchate to ungulate is sometimes very puzzling. 



2. FOMES ANNOSUS (Fries) Cooke 



Pileus woody, dimidiate, very irregular, conchate to applanate, 

 10-13 X 5-8 X 0.5-2 cm.; surface at first velvety, rugose, 

 anoderm, light-brown, becoming thinly encrusted, zonate, and 

 finally black with age; margin pallid, acute, becoming thicker; 

 context soft-corky to woody, white, 0.3-0.5 cm. thick; tubes 

 unevenly stratified, 2-8 mm. long each season, white, mouths 

 subcircular to irregular, 3-4 to a mm., edges rather thin, entire, 



