Summary:
Features include 1) resupinate growth on conifer wood, 2) a fruitbody that is reddish gray then purple gray or dark violaceous gray, the surface more or less tuberculate, 3) a detaching margin that is narrow and white soon darkening to brown, 4) spores that are allantoid, smooth, and colorless, 5) thick-walled encrusted cystidia but no gloeocystidia, and 6) a monomitic hyphal system, the hyphae with clamp connections, the subhymenium with vertical hyphae, and the subiculum with horizontal hyphae. The Burt description is for the synonym Peniophora separans Burt, which Burt described from a log in BC.

Microscopic:
SPORES 7-8.8 x 2.3-2.8 microns, allantoid, smooth, colorless, thin-walled; BASIDIA 4-spored, 30-40 x 5-7 microns, subcylindric, slightly constricted and sinuous, with basal clamp connection; CYSTIDIA usually numerous, at first thin-walled and colorless, then "with an outer encrustation and an inner crystalline filling in the distal part, basally not encrusted and with thick, brown walls", "cystidia larger in first hymenial layer (encrusted part reaching 35 x 15 microns), smaller in the later layers" (20-25 x 5-8 microns), sulfocystidia not seen; HYPHAE monomitic, 3-4 microns wide, with clamp connections, young hyphae thin-walled, colorless, "old ones with thickened brown walls", "subhymenium thickening of vertically arranged hyphae together with residua of basidia and of old cystidia forming a pseudoparenchymatic tissue", subiculum 40-100 microns thick, "partly even more, composed of densely united, mainly horizontal and parallel hyphae with thick, brown walls", (Eriksson), SPORES 8-10 x 2-3 microns, colorless, smooth; no gloeocystidia or conducting hyphae, CYSTIDIA numerous, 40-50 x 8-15 microns, encrusted, immersed, starting from base of hymenial layer; "in section 300-350 microns thick, colored, stratose, each stratum 2-layered, the supporting layer composed of densely and longitudinally interwoven, slightly colored hyphae 3 - 3 1/2 microns in diameter, the hymenial layer 75-120 microns thick, composed of densely arranged, erect tissue", (Burt)

Notes:
Peniophora piceae found in BC, AB, NB, NF, and MN, (Ginns). It is widespread and locally abundant in the continental Europe, and has been found once in Sweden, (Eriksson).