1925] 



BURT THE THELEPHORACEAE OF NORTH AMERICA. XIV 345 



substratum. Its most noteworthy character, by which it may 

 be recognized at a glance, is its curious habit of forming the 

 fructification on bark-covered limbs between the bark and the 

 wood, so that the loosened bark very noticeable on Quercus 

 limbs curls back, disclosing the fructification closely adnate on 

 the wood. The antler-shaped branching paraphyses occur in 

 P. phyllophida also. 



Specimens examined : 

 Washington: Bingen, W. N. Suksdorf, 910, type, 756, 757, 758. 

 Oregon: Corvallis, C. Epling (in Mo. Bot. Gard. Herb., 60183), 



S. M. Zeller, 1769, 2258 (in Mo. Bot. Gard. Herb., 56846, 



63028). 



115. P. nuda (Fr.) Bresadola, I. R. Accad. Agiati Atti III. 3: 

 114. 1897; Bourdot & Galzin, Soc. Myc. Fr. Bui. 28: 405. 

 1913; Rea, Brit. Basid. 695. 1922. 



Thelephora nuda Fries. Syst. Myc. 1: 447, 1821. Corticium 

 nudum Fries, Epicr. 564. 1838; Patouillard, Tab. Anal. Fung. 

 2: 33. /. 582. 1887; Sacc. Syll. Fung. 6: 626. 1888. Penio- 

 phora ochracea Massee, Linn. Soc. Bot. Jour. 2.5: 150. 1889, 

 but not Corticium ochraceum Fries. 



Illustrations: Patouillard, loc. cit. 



Fructification effused, closely adnate, very thin, pale drab- 

 gray, pale purplish gray or pale gull-gray, pruinose, waxy, crack- 

 ing in drying; in section brownish, darker and opaque next the 

 substratum, 75-160 y. thick, the hyphae densely interwoven, 

 rather erect, 3 y. in diameter, somewhat colored; cystidia in- 

 crusted, in all regions of the fructification, usually about 20-25 

 X 6 [a, larger near the substratum and sometimes up to 15 [a in 

 diameter; spores hyaline, even, curved, 4J^-9 X 23^-3 [l, re- 

 ported larger by European authors. 



Fructifications 2-6 X 1-2 cm. 



On fallen limbs of frondose species such as Acer, Quercus, 

 Populus, etc. Canada to Texas, in Europe and Japan. April 

 to January. Occasional. 



I have seen no authentic specimens of P. nuda, but the Euro- 

 pean concept of this species differs from P. cinerea in having the 

 fructifications more whitish gray in color, more broadly effused, 



