Hymenophore annual, membranous, loosely attached, effused, forming irregular areas to 10 x 6 cm.; surface pallid tan, polished, even, sparsely creviced when dry; margin thinning out, fibrillose, crenate, tan or bay brown, loosely attached. Context ferruginous, 300-400 µ thick, composed of a narrow layer of basal parallel hyphae, and an intermediate layer of woven hyphae branched at a wide angle, becoming vertically arranged beneath the hymenium; generative hyphae 6-8 µ diameter at the base, tapering towards the hymenium where 3-4 µ diameter, wall 0.25-0.5 µ thick, naked, fuscous, septate, practically without clamp connections. Hymenial layer to 60 µ deep, of basidia and paraphyses arranged in a dense palisade. Basidia subclavate, 20-35 x 5-7 µ, 4-spored, not projecting; sterigmata slender, to 4 µ long. Paraphyses cylindrical or subclavate, narrower than the basidia, often with fuscous walls. Spores elliptical, 4.5-6 x 2-2.5 µ, wall smooth, hyaline, 0.2 µ thick.

DISTRIBUTION. New Zealand.

HABITAT. Effused on bark and decorticated decaying wood.

Hymenophorum membranaceum, laxe adjunctum, effusum; superficie pallide alutacea, vernicosa, raro rimosa siccitate. Contextus ferrugineous, hyphis afibulatis, fuscis, 3-41 µ diam. sub hymenio, 6-8 µ prope basim, nudis. Basidia 20-35 x 5-7 µ, 4 sporis. Sporae ellipticae, 4.5-6 x 2-2.5 µ, laeves, hyalinae.

Recognized readily by the fuscous hyphae, since it is the only species in the region with coloured hyphae. Context hyphae are 6-8 µ diameter at the base and taper gradually until beneath the bymenium they are 3-4 µ. Though listed in the section without clamp connections these are present, but occur so rarely that the plant would normally be sought herein. Only one clamp connection was seen in a section which contained 430 septa, and in other sections of similar size none was noted. Bridging hyphae are common.

Litsaea calicaris (Sol.) Benth. & Hook. f. Auckland: Waiotapu, June, 1950, J.M. Dingley, type collection, P.D.D. herbarium, No. 10589.