Acacia dealbata Link. Auckland: Tinopai, 100ft., April, 1947, J.D. Atkinson. Coriaria arborea Linds. Auckland: Kohekohe, Waiuku, February, 1953, J.M, Dingley, Leptospermum cricoides A. Rich. Auckland: Hautepe, Taupo, March, 1953, J.M. Dingley. Macropiper excelsum (Forst. f.) Miq. Auckland: Hick's Bay, 300ft., May, 1952, G.H.C. Melicytus ramiflorus Forst. Auckland: Huia, July, 1953, J.M. Dingley. Meryta sinclairii (Hook. f.) Seem. Auckland: South-west King Island, January, 1952, E.E. Chamberlain. Nothofagus cliffortioides (Hook. f.) Oerst. Auckland: Whakapapa, Mt. Ruapehu, 3,000ft., October, 1949, J.M. Dingley, type collection, P.D.D. herbarium, No. 11220. Otago : Routeburne Valley, February, 1948, J.M. Dingley. Nothopanax arboreum (Forst. f.) Seem. Auckland. Mt. Ruapehu, 3,000ft. October, 1949, J.M. Dingley. Rubus sp. Wellington: Ohakune, 2,000ft., December, 1953, J.M. Dingley.

Hymenophore annual, adnate, ceraceous, effused, forming linear areas to 30 x 4 cm.; surface cream, becoming straw colour, pallid ochre or buff, even, at length creviced then tending to lift at creviced edges; margin thinning out, membranous, white, adnate. Context white, 75-500 µ thick, composed of a narrow basal layer of parallel hyphae, and an intermediate layer of vertical hyphae densely arranged, some crystal coated near the base and embedded in masses of crystals, or the latter may be wanting; generative hyphae 4-6 µ diameter, wall 0.5 µ thick, hyaline, branched, septate, with clamp connections. Hymenial layer 60-90 µ deep, of basidia, paraphyses and gloeocystidia. Basidia clavate, 24-48 x 5-8 µ, 2-4-spored; sterigmata slender, to 10 µ long. Paraphyses subclavate, same length but narrower than the basidia. Paraphysate hyphae scanty, cylindrical. Gloeocystidia arising from the context and projecting 30-70 µ, cylindrical with rounded apices, sometimes slightly moniliform, or strangulated near apices, 60-150 x 8-12 µ, wall to 1 µ thick. Spores long-elliptical, 10-16 x 4-6 µ, wall smooth, hyaline, 0,25 µ thick.

DISTRIBUTION. New Zealand.

HABITAT. Effused on bark of dead branches.

Hymenophorum ceraceum, adnatum, effusum; superficie cremea deinde pallide ochracea vel bubalina, aequa, demum rimosa. Hyphae contextus fibulatae, 4-6 µ diam., aliquot prope basim crystallis tectae, interdum in crystallis sitae. Basidia 24-48 x 5-8 µ, 2-4 sporis. Gloeocystidia ad 70 µ eminentes, cylindricalia, termini rotundis, aliquot prope apices constricta, 60-150 x 8-12 µ. Sporae longo-ellipticae, 10-16 x 4-6 µ, laeves, hyalinae.

Large elliptical spores with one prominent guttula and long, stout, cylindrical gloeocystidia projectiing 40-70 µ are the main diagnostic features. When well developed and filled with oily contents gloeocystidia are conspicuous bodies in sections; but in old specimens they collapse and are sometimes difficult to detect. Tissues of the context become somewhat gelatinized when old, and tend to become pseudoparenchymatous. Crystals may be present then forming masses near the base and coating some of the context hyphae; in other collections they may be wanting.

Auckland: Whakapapa, Mt. Ruapehu, 3,000ft., October, 1949, J.M. Dingley, type collection, P.D.D. herbarium, No. 11220.

The species belongs to Hyphoderma Wallr. and the name is a later synonym of Hyphoderma assimile (H. S. Jacks. & Dearden) Donk. Nakasone (1984) referred the species to Crustoderma Parm., but it deviates quite strongly from the type species, C. dryinum (Berk. & Curt.) Parm. and also from Nakasone's generic description. The basidia are not narrowly clavate or cylindrical, but suburniform and the spores are typical Hyphoderma spores and not thick-walled at all. The type of rot was indistinct in the material studied.