1926) 



BURT THELEPHORACEAE OF NORTH AMERICA. XV 281 



somewhat colored but concolorous with the surface of the hy- 

 menium, very compact, supported by the broad layer of loosely 

 arranged, obliquely ascending, thin- walled hyphae 3-4 y. in 

 diameter, sometimes conspicuously guttulate, nodose-septate, 

 not incrusted; no gloeocystidia; spores hyaline, even, 7-10 X 4- 

 6 (i, flattened on one side, tapering towards the pointed base, 

 usually glued together on the flattened side at ends of the pro- 

 truding basidia. 



Fructifications 1-10 cm. long, 1-5 cm. wide, rarely only 1-3 

 mm. in diameter. 



On bark of fallen decaying limbs of many frondose species. 

 Europe and northern United States and Canada. Throughout 

 the year. Very common. 



C. laeve is a very common species on fallen limbs of poplar, 

 maple, beech, etc., whose usually drab fructifications crack when 

 dried and show the dark hymenial crust supported on a whitish 

 subiculum. The absence of paraphyses and presence of spores 

 7-10 X 4-6 [ij shaped like apple seeds and glued together in 

 groups of 2-4, are important additional characters. In the large 

 number of gatherings cited below there are only 2 American 

 specimens which have a slightly reflexed margin and would be re- 

 ferred to Stereum, where the species really belongs. 



Specimens examined: 

 Exsiccati: Brinkmann, Westfalische Pilze, 9; Cooke, Fungi Brit., 



10; Ell. & Ev., Fungi Col., 221, under the name Corticium 



glabrum; Libert, PL Crypt. Ard., 20; Romell, Fungi Scand., 



124; Sydow, Myc. Germ., 355, under the name Peniophora 



laevis; de Thiimen, Myc. Univ., 1109. 

 Sweden: Svex. Soderm., Lindblad, authentic specimen of C. evol- 



vens from Fries (in Kew Herb.) ; Stockholm, L. Romell, 89, 90, 



91, 92, 93, 94, 95, and in Romell, Fungi Scand., 124. 

 Finland: Mustiaia, P. A. Karsten, in de Thiimen, Myc. Univ., 



1109. 

 Germany: Brandenburg, H. Sydow, in Sydow, Myc. Germ., 355; 



Westphalia, W. Brinkmann, in Brinkmann, Westfalische 



Pilze, 9. 

 Austria: Innsbruck, Tirol, V. Litschauer, 3 specimens. 

 Italy: Trient, G. Bresadola, 3 specimens; Vallambrosa, Cavara, 



comm. by Bresadola. 



