WESTERN POLYPORES 13 



edges at first thick, becoming thin and often dentate with age; 

 spores cylindric, subcurved, 7-8 X 2-3 n; stipe central, solid, 

 woody, equal, squamulose, avellaneous, not black at the base, 

 2-3 cm. long, 3-7 mm. thick. 



Reported from California by Harkness. The species occurs on 

 fallen dead wood of deciduous trees. 



3. POLYPORUS COLUMBIENSIS Berk. 



Pileus circular, very thin, subinfundibuliform, 2.5 X 0.05 cm.; 

 surface brown, very smooth and glabrous, resembling parchment 

 or the skin of an apple; margin thin, acute, straight, undulate; 

 context pallid, membranous; tubes decurrent, very short, dark- 

 brown in the type specimens, mouths minute, angular, 5 to a mm., 

 edges thin, acute; stipe central, slender, concolorous, finely 

 velvety, tough and fibrous, 1-5 cm. long, 3 mm. thick. 



Not reported since its original discovery on dead wood on the 

 Columbia River in Oregon. 



4. POLYPORUS OSSEUS Kalchbr. 



Hymenophore cespitose-multiplex, elastic- tough, at length 

 indurate; pilei subdimidiate, variable in size and shape, convex 

 or depressed, 5 cm. or more broad; surface white, smooth, 

 glabrous; context white, rather thick, with an acid odor, becoming 

 very hard when dry ; tubes decurrent, white, becoming discolored, 

 mouths circular, minute, edges at length lacerate ; spores 5 n 

 long; stipe short, arising from a common base and more or less 

 united. 



This species occurs on trunks and stumps of larch and certain 

 other trees in Europe, and is occasional in this country in a few 

 states along the Canadian border. It may be looked for in 

 Washington and British Columbia. When dry, it is as hard as a 

 bone, as the name implies. 



5. POLYPORUS ZELLERI Murrill, sp. nov. 



Pileus flabelliform, nearly plane, imbricate-cespitose, 4-6 X 

 6-8 X 0.3-0.5 cm.; surface pruinose or slightly innate-fibrillose, 

 becoming glabrous, not shining, isabelline-avellaneous, margin 

 thin, concolorous, subentire, becoming somewhat inflexed and 

 undulate on drying, not ciliate; context white, corky, homoge- 

 neous, tubes white or slightly discolored, about I mm. long, 

 subcylindric, mouths angular, very minute, edges thin, lacer- 



