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 
eystidia. 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, 
508, 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 pezizaeform, 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 ui (AUD f il 
side to the substratum, or the margin on M M AS i "T n 
the upper side may grow outward so as VU AI, ir il, 
to form umbonate, sessile pilei attached Hi WN 
by the umbo and lower side, with the 
upper surface narrowly concentrically Pie 28 ee een 
sulcate, mummy-brown to fuscous; hy- Section of type, X 90. 
9 
