1920 ; 



BURT THELEPHORACEAE OF NORTH AMERICA. XII 151 



hymenium even, warm buff at first, sometimes becoming pale 

 smoke-gray, unchanged when cut or bruised; in structure 

 500-700 ix thick under the hairy covering, with the inter- 

 mediate layer bordered next to the hairy covering by a very 

 dense, narrow, golden zone, the rest of the intermediate layer 

 composed of densely and longitudinally arranged hyaline hyphae 

 3-4 m in diameter, some of which in the subhymenium are thick- 

 walled, up to 5-6 m in diameter, and very rarely have golden- 

 brown contents as seen between the basidia; no colored con- 

 ducting organs, cystidia, nor gloeocystidia; spores white in spore 

 collection, even, flattened on one side, 5-7|X2-2f n. 



Reflexed portion varying from barely reflexed up to 2 cm. 

 broad, 1-2 cm. long; fructifications merely gregarious or con- 

 fluent, and imbricated. 



On logs and stumps of birch, beech, and other frondose 

 species. Newfoundland to South Carolina and westward to 

 British Columbia and California, and in Mexico. July to 

 November in the east and to February in the Pacific states. 

 Common. 



Stereum hirsutum is characterized by its strigose-hirsute, 

 buff-colored pileus, weathering more or less gray, and by its 

 warm buff hymenium, sometimes smoke-gray, which does not 

 exude a red juice when wounded; as in S. rameale, S. versicolor, 

 S. fasciatum, S. lobatum, S. australe, and S. gausapatum, the 

 upper surface of the intermediate layer is differentiated into a 

 thin, golden, somewhat horny crust from which the hairy cover- 

 ing springs. This golden zone shows well under the microscope, 

 and its presence is a decisive character for separating S. hir- 

 sutum from the southern S. sulphuratum, a species of somewhat 

 similar aspect. 



Specimens examined: 

 Exsiccati: Berkeley, Brit. Fungi, 146; Cavara, Fungi Longo- 

 bardiae, 61; Cooke, Fungi Brit., 108; Ellis, N. Am. Fungi, 

 1204; Krieger, Fungi Sax., 118; Rabenhorst, Herb. Myc, 

 211; Romell, Fungi Scand. Exs., 26. 

 Sweden: Femsjo, L. Romell, two collections, and E. A. Burt; 

 Mauritzberg, W. A. & E. L. Murrill, 4078 (in N. Y. Bot. 

 Gard. Herb, and Mo. Bot. Gard. Herb., 56671); Stock- 

 holm, L. Romell, 30, Ifil, and in Romell, Fungi Scand. 

 Exs., 26. 



