1916] 



BURT THELEPHORACEAE OF NORTH AMERICA VI 217 



Type: in Herb. Schweinitz. 



Fructification effused, soft, felty-membranaceous, separa- 

 ble, in color varying from Saccardo 's umber to bister, rarely 

 fuscous, the margin thinning out and barely 

 determinate; in structure 200-1200/a thick, 

 with hyphae concolorous with the fructifica- 

 tion, thick-walled, even, loosely interwoven, 

 branching at a wide angle, abundantly no- 

 dose-septate, 4%-5/M in diameter or rarely 

 6fi ; basidia with 4 sterigmata ; spores con- Fig. 7 



colorous, globose, or subglobose and flattened "Hvpha^^s^ore* 

 on one side, echinulate, about G/x in diameter, x640. 



or 6-9 X 6-7 fi. 



Fructifications 410 cm., and more, long, 2-5 cm. broad. 



On rotten wood and bark of both frondose and coniferous 

 species. Canada to North Carolina and westward to Mon- 

 tana, and in Bahama Islands. July to November. Probably 

 common. 



H. spongiosus belongs in the group with H. fuscus, H. um- 

 hrinus, and H, spiniferus. The absence of a vinaceous com- 

 ponent in its color is a useful character for separation at a 

 glance from H. fuscus. If the surface of H. spongiosus is 

 viewed with a lens, the component fibers are seen running 

 in all directions, as in felt or blotting paper. H. iimbrinus 

 has its hyphae lacking clamp connections, i. e., not nodose- 

 septate, and its basidia form a compact hymenium. H. spin- 

 iferus differs by having its hyphae spiny. 



Specimens examined: 

 Finland: Mustiala, P. A. Karsten, authentic specimen of 



Hypochnus obscuratus. 

 Canada: Quebec, Ironsides, J. Macoun, 255, 

 New Hampshire: Chocorua, W. G. Farlow, 14. 

 Vermont: Middlebury, E, A, Burt, three collections; Lake 



Dunmore, E. A. Burt. 

 New York: Albany, E. D. House (in N. Y. State Mus. Herb. 



and in Mo. Bot. Gard. Herb., 15833). 

 North Carolina: ScMveinitz, type (in Herb. Schweinitz). 

 Indiana: Miller, E. T. S. A. Harper, 758. 



