1916] 



BURT THELEPHORACEAE OF NORTH AMERICA. VH 



337 



Grenada: Grand Etang, R, Thaxter, comm. by W. G. Far- 

 low, a (in Mo. Bot. Gard. Herb., 43912). 



12. S. frustulosum (Berk. & Curtis) Patouillard, Soc. Myc. 

 Fr. Bui. 10:79. pi, 3. f. 4. 1894. 



Hymenochaete frustulosa Berk. & Curtis, Linn. Soc. Bot. 

 Jour. 10:334. 1868; Sacc. Syll. Fung. 6:601. 1888. 



Illustrations : Patouillard, loc, cit. 



Type: type and cotype in Kew Herb, and Curtis Herb. 



Fructification resupinate, effused, coriaceous, dry, velutin- 

 ous, honey-yellow to old gold, repeatedly divided into many 

 narrow, sinuous, reticulate di- 

 visions which are more dis- 

 tinct towards the margin; in 

 structure about 600-700/x thick, 

 3-layered, with next to the 

 substratum a broad layer, up 

 to 200/A thick, with hyphae 

 densely longitudinally ar- 

 ranged, 2/A in diameter, concol- 

 orous with the fructification, 

 which ascend, without forming 

 pillars, as (2) the loosely ar- 

 ranged middle layer, whose hy- 

 phae pass into and form (3) 

 the hymenial crust which is finally very dense and compact in 

 fully developed specimens, about 200/x thick, with hyphae 

 concolorous, even, 11/2-2/* in diameter, branching towards 

 the surface into flexuous branches, or paraphyses, about 1/* 

 in diameter, once or twice dichotomously branched and with 

 tips curved or spirally coiled; probasidia borne laterally on 

 the hyphae, hyaline, pyriform, 9 X 5%/^? becoming elongated 

 and septate as a few-celled, spore-bearing organ, or producing 

 directly a sterigma bearing one spore ; spores hyaline, even, 

 cylindric, nearly straight, 13-17 X 4r-5/>t. 



Fructifications up to 10 cm. long, 1-2 cm. broad, less than 

 1 mm. thick. 



22 



Pig. 9 

 S. frustulosum. 

 a, probasidia; b, three spore-bear- 

 ing organs; n, septate colored or- 

 gan; p, paraphyses; r, probasidium 

 bearing a spore; s, spores. X 640. 



