158 Journal of the Mitchell Society [February 



when dry a warm buff to buffy brown, usually darker in center. 

 Surface even, pulverulent, sparingly cracked in places; context made 

 up of loosely packed, thin-walled, hyaline hyphae 2-3.7[jl thick; 

 hymenium closely packed. No cystidia and no crystals present. 



Spores fuscous in a good spore-print, smooth, elliptic with a dis- 

 tinct mucro, 6.6-7.2 X 9.3-1 Llpi. Basidia club-shaped, swollen 

 considerably at the distal end; extending out above the hymenium 

 up to 20[JL (counting the sterigmata) ; 8.5[x thick, sterigmata 4, prong- 

 like, curved. 



4219. On bark and wood of dead pine, March 23, 1920. 

 4235. On bark of pine log, April 15, 1920. 



PENIOPHORA 



Entirely resupinate as a thin encrusting layer, as in Corticium, 

 but differing from the latter in having specialized cystidia included 

 in the hymenium and usually projecting as far as the basidia or 

 beyond them. We are including one (P. alhomarginata) which often 

 has a narrowly reflexed margin. The cystidia are commonly warted 

 on the distal half, in which case they are easily distinguished. Spores 

 smooth, white or (when fresh) pink. Hymenochaete differs in having 

 dark, smooth, spine-like setae projecting far above the basidia. The 

 pink color shown by a fresh spore print in several species we have 

 studied fades out after a few months in the herbarium. We have in- 

 cluded six species to represent the genus, which is a large one and 

 often difficult to distinguish from Corticium. See Massee in Journ. 

 Linn. Soc. (Bot.) 25: 140. 1889; Bourdot and Galzin, Bull. Soc. Myc. 

 Fr. 28: 372. 1912; Cooke, Grevillea 8: 17. 1879; Bresadola, Ann. Myc. 

 1: 100. 1903 (as Kneiffia). See also Gleocystidium as treated by 

 Bourdot and Galzin in Bull. Soc. Myc. Fr. 28: 354. 1912. This last 

 genus includes species usually treated under Peniophora, but its rec- 

 ognition, as Burt has well said, would lead to difficulties without com- 

 pensating advantages. Other proposed genera as Peniophorella and 

 Gloeopeniophora have similar objections. For a species parasitic on 

 chrysanthemum {Corticium (Peniophora) Chrysanihemi Plowr.) see 

 Trans. Brit. Myc. Soc. for 1904, p. 90. 1905. 



Key to the Species Treated 



On pine wood, making an extensive, pale, sub-translucent, 

 parchment -like membrane when dry; sub-waxy when 

 wet P. gigantea (1) 



