1926] 



BURT THELEPHORACEAE OF NORTH AMERICA. XV 305 



1892; I. R. Accad. Agiati Atti III. 3: 112. 1897; Sacc. Syll. Fung. 

 11: 126. 1895. Kneiffia cerussata Bresadola, Ann. Myc. 1: 104. 

 1903. 



Type: in Burt Herb., an authentic specimen which is probably 

 a part of the type. 



Fructifications effused, closely adnate, thin, waxy, white at 

 first, becoming between pinkish buff and cream-buff in the her- 

 barium, even, somewhat pruinose under a lens, cracking at right 

 angles when old into masses about 3-4 to a mm., the margin 

 similar, thinning out; in section 100-150 \i thick; not colored, 

 composed of suberect, interwoven, densely crowded hyphae about 

 2 [jl in diameter and of very numerous gloeocystidia; gloeocystidia 

 flexuous, 40-60 X 4-6 |i; bottle-brush paraphyses form the 

 hymeniai surface; spores hyaline, even, 12-15 X 7-8 \l. 



Fructifications 1-7 cm. long, 2-10 mm. wide. 



On old, weathered, coniferous wood. Europe, Manitoba, and 

 Oregon. June to October. 



C. cerussatus is distinguished from our other species of Aleuro- 

 discus with the exception of A. succineus, by having both gloeo- 

 cystidia and bottle-brush paraphyses and from the latter by being 

 effused. 



Specimens examined : 

 Italy: Trient, G. Bresadola, part of type probably. 

 Manitoba: Binscarth, G. R. Bisby, 1050 (in Mo. Bot. Gard. Herb., 



59037); Winnipeg, G. R. Bisby, 65 (in Mo. Bot. Gard. Herb., 



57899), and comm. by L. O. Overholts, 7027 (in Mo. Bot. 



Gard. Herb., 57475). 

 Oregon: Granite Pass, J. R. Weir, 8682 (in Mo. Bot. Gard. Herb., 



36743). 



A. disciformis (DC.) Patouillard, Soc. Myc. Fr. Bui. 10: 80. 

 textf. 1894; v. Hohnel & Litschauer, K. Akad. Wiss. Wien Sitz- 

 ungsber. 116: 798. pi 1, f. 1. 1907; Bourdot & Galzin, Soc. 

 Myc. Fr. Bui. 28: 350. 1913; Rea, Brit. Basid. 671. 1922. 



Thelephora disciformis De Candolle, Fl. Fr. 6: 31. 1915; Fries, 

 Syst. Myc. 1: 443. 1821 Stereum disciforme (DC.) Fries, 

 Epicr. 551 . 1838 ; Hym. Eur. 642. 1874 ; Patouillard, Tab. Anal. 

 Fung. 112./. 250. ISSi.Peniophora disciformis (DC.) Cooke, 



