[Vol. 13 

 336 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



surface upon which growing, the margin somewhat fimbriate; in 

 section 200-400 (i thick, not colored, composed of densely inter- 

 woven, hyaline hyphae about 2J^ y. in diameter, with the wall 

 gelatinously modified, much foreign matter present; cystidia not 

 incrusted, cylindric, obtuse, 3J^ 7 y. in diameter, protruding up 

 to 30 \l ; basidia longitudinally septate, pyriform, 15 X 9 \i f present 

 in the surface of the hymenium; spores simple, hyaline, curved, 

 7-8 X 33^-4 [i, copious. 



Fructification 3 cm. long, 2 cm. wide. 



Running over wood humus on the forest floor at 7000 feet 

 altitude. Mexico. December. 



S. fibrillosa is a small, whitish, incrusting species running over 

 the irregular surface of wood humus. Its distinguishing char- 

 acter is the presence of cystidia, which are conspicuous and as 

 distinct as in a Peniophora, and locate this species in the subgenus 

 Heterochaelella of Sebacina. 



Specimens examined: 

 Mexico: Tepeite River region, near Guernavaca, W. A. & E. L. 



Murrill, 515, type (in N. Y. Bot. Gard. Herb., and Mo. Bot. 



Gard. Herb., 54514). 



S. lactescens Burt, n. sp. 



Type: in Mo. Bot. Gard. Herb, and Farlow Herb. 



Fructifications effused, rather thick when moist, thin when 

 dry, gelatinous, separable, loosely attached, drying between 

 drab and wood-brown, even, the margin thinning out; in section 

 1000 [i thick, not colored, composed of densely arranged, as- 

 cending and interwoven hyphae with walls so completely modified 

 gelatinously that only the protoplasmic contents of the lumen 

 can be followed; gloeocystidia somewhat colored, clavate, 54 X 5- 

 7}^ \l, abundant in the hymenium; basidia longitudinally cruci- 

 ately septate, 15 X 12 ^, immersed about 25-35 y. below the 

 surface of the hymenium; spores hyaline, even, curved, 12 X 6 \l. 



Fructifications 2 cm. long, J/-l cm. wide. 



Longitudinally confluent on the under side of a frondose limb. 

 West Indies. 



S. lactescens may be recognized by its wood-brown color when 

 dry, gelatinous consistency, and numerous and conspicuous, 



