1915] 



BURT THELEPHOBACEAE OP NORTH AMERICA. V 753 



Type: authentic specimens of ThelepJiora incrustans and 

 Merisma cristatum from Persoon in Kew Herb. 



Fructifications coriaceous-fleshy, varied in form, creeping 

 on the ground and ascending and incrusting small erect 

 objects and forming little columns and free branches, the 

 apices somewhat awl-shaped or fringed, or effused and resup- 

 inate on bark, whitish, drying warm buff ; structure in section, 

 250-400 {I thick, (1) with a broad layer of very loosely inter- 

 woven rather stiff hyphae, 2-2^ /x in diameter, which divide 

 above into fine branches and form (2) a densely interwoven 

 layer about 60-150 /* thick with the basidia in the upper 40-90 

 H among the very fine (1^ ix in diameter), densely crowded, 

 somewhat interwoven filaments from the subhymenium; 

 basidia longitudinally septate, ovoid or pyrif orm, 12-20 X 9- 

 14 n ; spores colorless, simple, even, flattened on one side or 

 curved, 12-14 X 6-8 n. 



Fructifications 5-6 cm. long, 2-5 cm. wide, ascending ob- 

 jects 2-5 cm. ; pileate flaps, when present, ^1 cm. long. 



On the ground in woods and incrusting objects, and resup- 

 inate on logs. Canada to Louisiana and westward to Mis- 

 souri. June to October. Common. 



S. incrustans is the common incrusting Sehacina of Eastern 

 North America. It may usually be recognized at sight by 

 coriaceous-fleshy consistency, occurrence on earth and run- 

 ning up and incrusting living objects, and pallid color. The 

 thinner hymenial layer, paraphyses less rod-like in form, and 

 finer and thinner-walled hyphae of layer next to the sub- 

 stratum afford structural characters separating specimens of 

 this species from those of 8. chlorascens and S. Helvelloides. 



I exclude from the synonymy of S. cristata, Clavaria 

 laciniata of BuUiard's 'Hist. Champ.' 1:208. pi. 415. f. 1, 

 because in the absence of authentic specimens and observa- 

 tions in regard to spores and basidia, it is not certain that C. 

 laciniata Bull, is Merisma cristatum. Bulliard 's figures repre- 

 sent quite as well an incrusting European fungus communi- 

 cated to me by Bresadola under the name Thelephora fas- 

 tidiosa (Pers.) Fr., which has simple basidia and colorless 

 echinulate spores. This species is the Thelephora cristata 



