1920] 



BURT THELEPHORACEAE OF NORTH AMERICA. XII 223 



paraphyses, the location of the cystidia in the hy menial side of 

 the fructification, and the velvety surface sharply separate 

 wholly resupinate specimens of S. versiforme from brownish 

 colored forms of Peniophora cinerea. 



Peniophora obscura (Pers.) Bresadola, according to specimen 

 collected in Hungary, communicated to me by Bresadola and 

 compared by him with an authentic specimen of Persoon, is 

 strikingly similar to very young and wholly resupinate specimens 

 of Stereum versiforme. There is no European record that P, 

 obscura ever has been observed reflexed or has shown any ten- 

 dency to become reflexed. In America, S. versiforme is wholly 

 resupinate only when very young and soon thickens, becomes 

 more or less reflexed, and in well-developed specimens such as 

 that cited below, collected by Underwood at White Plains, N. Y., 

 has but little in common with P. obscura. For these reasons I 

 believe that the name Stereum versiforme should be applied to 

 American specimens until Europeans find their Peniophora 

 obscura in a reflexed stage identical in its characters with S. 

 versiforme. 



Specimens examined: 

 Exsiccati: Ellis, N. Am. Fungi, 606, under the name Stereum 



papyrinum; Ell. & Ev., N. Am. Fungi, 3209; Ell. & Ev., 



Fungi Col., 611; de Thumen, Myc. Univ., 307. 

 Canada: J. Macoun, 8 in part, 70; on peach tree, J. H. Fault 



(in Mo. Bot. Gard. Herb., 55561). 

 Quebec: Hylmer, J. Macoun, 229. 

 Ontario: York Mills, J. H. Fault, Univ. Toronto Herb., 322 in 



part (in Mo. Bot. Gard. Herb., 44933). 

 New Hampshire: Chocorua, W. G. Farlow (in Mo. Bot. Gard. 



Herb., 55586). 

 Vermont: Ripton, E. A. Burt. 

 Massachusetts: Arlington Heights, E. A. Burt; Sharon, A. P. 



D. Piguet, comm. by W. G. Farlow (in Mo. Bot. Gard. 

 Herb., 55231); Waverly, A. B. Seymour, T 15 (in Mo. 

 Bot. Gard. Herb., 18098). 



New York: Alcove, C. L. Shear, 1139, 1304, 1328; East Galway, 



E. A. Burt; Grand View, H. von Schrenk (in Mo. Bot. Gard. 

 Herb., 42807); Ithaca, Van Hook, comm. by G. F. Atkin- 

 son, 8217; Karner, H. D. House (in N. Y. State Mus. Herb. 



