Overholts: Diagnoses of American Porias 5 



Poria ferruginosa (Schrad.) Fr., Syst. Myc. i: 378. 1821 



Description, Fries, I. c: Effusus, crassus, ferrugineo-spadiceus, 

 poris subrotundis inaequalibus. 



Inaequalis, saepe interruptus, durus, J4— 1 nnc. crassus, omnino 

 excarnis. Pori mediae magnitudinis, subobliqui, acute. 



Ad truncos Alneos. Aest. 



Redescription: Effused for several centimeters on decorticated 

 wood or rarely on bark; annual or at times perennial, 0.5-5 mm - 

 thick, mostly inseparable, when young and growing with a brown 

 tawny pubescent margin less than 1 mm. .broad, when mature losing 

 this and becoming entirely fertile ; subiculum very thin, usually not 

 more than 0.5 mm. thick, fibrous, scarcely discernible in thin fructi- 

 fications ; tubes frequently oblique, in one or rarely as many as 

 four layers, 1-2 mm. long each season, not distinctly stratified in 

 perennial specimens, brown within or the older layers somewhat 

 whitish pubescent under a lens; the mouths cinnamon, sayal brown, 

 or snuff brown, usually entirely without sheen though in some 

 specimens a slight silkiness may be detected, unchanging on drying 

 and the colors constant in herbarium specimens, subcircular to sub- 

 angular, the dissepiments at most of only medium thickness and 

 becoming thinner at maturity, even and entire except where grow- 

 ing in oblique situations, averaging 4-6 per mm. ; spores oblong- 

 ellipsoidal or oblong, hyaline, 4.5-5x2-3^; setae more or less 

 abundant, rather short and sharp pointed, typically projecting 15- 

 30 ll beyond the basidia, 5-7 ll diameter ; hyphae straight and rigid, 

 brown, no cross walls except rarely in the young hyphae, no clamps, 

 simple, 2-3 fx diameter. 



On dead wood of Acer, Alnus, Fag us, Prunus, Populus, Salix, 

 Ulmus, Quercus, Betulct, Ostrya, and perhaps other deciduous 

 trees. 



Specimens Examined: North Conway and Crawford Notch, 

 N. H. ; Cold Spring Harbor, Cranberry Lake. Vaughns, Karner, 

 Crown Point, and Mechanicsville, N. Y. ; Greenwood Furnace, 

 Pa.; Oxford and Cincinnati, Ohio; Ann Arbor and New Rich- 

 mond, Mich.; Edgemont, 111.; Evaro, Mont.; Bellingham, Wash.; 

 Ontario, Canada. 



Apparently the species may be expected on all kinds of deciduous 

 woods, but none have yet been seen on a coniferous substratum. 

 It appears to be a species more abundant in the north and no 

 specimens have been examined from south of Ohio. Ordinarily 



