1920] 



BURT THELEPHORACEAE OF NORTH AMERICA. XII 209 



face of soft, matted, interwoven hairs from the hyphae of the in- 

 termediate region, by its buff hymenium, and by its incrusted 

 cystidia. These incrusted cystidia and different aspect of the 

 fructifications afford sharp separation from S. ochraceo-flavum ; 

 S. ochroleucum and S. rugosiusculum have the general aspect of 

 S. spumeum but both lack incrusted cystidia, and S. rugosius- 

 culum has in its subhymenial region pyriform, vesicular organs. 

 S. spumeum is so frequently resupinate or very narrowly reflexed 

 that gatherings are likely to be referred to Peniophora. 



Specimens examined: 

 New York: Hudson Falls, S. H. Burnham, 27' (in Mo. Bot. 



Gard. Herb., 54486). 

 Pennsylvania: E. Michener, 1864 (in Curtis Herb., under the 



name Corticium giganteum). 

 South Carolina: Aiken, on oak limbs, H. W. Ravenel, 1772 (in 



Curtis Herb., under the name Corticium ochroleucum, 



" formerly C. spumeum"). 

 Louisiana: Baton Rouge, Edgerton & Humphrey; St. Martin- 



ville, A. B. Langlois,E, type 

 Mexico: Guernavaca, W. A. & E. L. Murrill, 405, 413, 414, 498, 



503, 520, comm. by N. Y. Bot. Gard. Herb, (in Mo. Bot. 



Gard. Herb., 54520-54523, 56685, 55524); Cordoba, W. A. 



& E. L. Murrill, 1214, comm. by N. Y. Bot. Gard. Herb. 



(in Mo. Bot. Gard. Herb., 54592). 



67. S. erumpens Burt, n. sp. Plate 6, fig. 67. 



Type: in Burt Herb. 



Fructifications corky, rarely resupinate, usually bursting out 

 from the inner bark as small pezizaef orm, orbicular disks or cups 

 with elevated black margins and cinereous or pallid neutral gray 

 hymenium; these fructifications may become crowded as if 

 confluent, and then broken up into frus- 

 tules and remain attached by the under 

 side to the substratum, or the margin on 

 the upper side may grow outward so as 

 to form umbonate, sessile pilei attached 

 by the umbo and lower side, with the 

 upper surface narrowly concentrically Fig 38 5> erumpens. 



sulcate, mummy-brown to fuscous; hy- Section of type, x 90. 



