Corynocarpus laevigata Forst. Auckland: Buffalo Beach, Whitianga, November, 1947, E.E. Chamberlain. Leptospermum ericoides A. Rich. Auckland: Kauri Glen, Northcote, August, 1951, J.M. Dingley. Leptospermum scoparium Forst. Auckland: Konini Road, Waitakeres, 1,000ft, July, 1947, J.M. Dingley. Nothofagus fusca (Hook. f.) Oerst. Westland: Ahaura, November, 1954, J.M. Dingley. Nothopanax arboreum (Forst. f.) Seem. Auckland: Mountain Road, Waitakeres, 600ft, July, 1950, J.M. Dingley. Pittosporum eugenioides A. Cunn. Auckland: Kaiwaka, May, 1949, J.M. Dingley; type collection, P.D.D. herbarium, No. 7351; Sprague's Hill, Henderson, 900ft. May, 1947, J.M. Dingley. Weinmannia racemosa L.f. Auckland: Kauaeranga Valley, Thames, August, 1954, J.M. Dingley.

Hymenophore annual or perennial, membranous, adnate, effused forming irregular linear areas to 10 x 6 cm, with a few scattered irregular islands; surface cream, becoming yellow-ochre, even, finally creviced irregularly and tending to lift along the edges of the fissures; margin thinning out, pelliculose-fibrillose, adnate, concolorous. Context white or cream, 160-400 µ thick, basal layer broad or narrow, of parallel hyphae, intermediate layer of ascending densely compacted hyphae and cystidia, when zoned of alternating layers of vertical and parallel hyphae; generative hyphae 3-4.5 µ diameter, walls 0.5 µ thick, hyaline, naked, branched, septate, with large clamp connexions. Hymenial layer to 45 µ deep, a close palisade of basidia, paraphyses, gloeocystidia and cystidia. Basidia subclavate, 18-25 x 4-5 µ, 4-spored; sterigmata slender, to 6 µ long. Paraphyses similar to but shorter than the basidia. Gloeocystidia somewhat scanty, confined to the hymenial layer, projecting to 30 µ, flexuous-cylindrical, 35-46 x 5-6 µ, walls 0.5 µ thick. Vesicles confined to the intermediate layer, numerous or scanty, pyriform, 6-12 µ diameter, walls 0-5 µ thick. Cystidia confined to the hymenium and subhymenium, not or scarcely projecting, conical, 40-60 x 12-20 µ, coarsely crystal coated. Spores pip-shaped, 5-6 x 2.5-3 µ, walls hyaline, smooth, 0.2 µ thick; commonly adhering in pairs or fours.

DISTRIBUTION. New Zealand.

HABITAT. Effused on bark of dead branches and stems.

Hymenophorurn annum, vel perenne, membranaceum, adnatum, effusum; superficie cremea deinde ochracea, aequa, inaequaliter rimosa. Hyphae contextus fibulatae, 3-4.5 µ diam., nudae. Basidia subclavata, 18-25 x 4-5 µ, 4 sporis. Gloeocystidia rara, flexuoso-cylindricalia, 35-46 x 5-6 µ. Vesiculis pyriformibus, 6-12 µ diam. Cystidia conica, 40-60 x 12-20 µ, crystallis crassis tecta. Sporae obovatae, attenuato-apiculatae, 5-6 x 2.5-3.5 µ, laeves, hyalinae.

Three species described herein possess vesicles in addition to gloeocystidia and cystidia. In P. vesiculosa and P. utriculosa vesicles are pyriform and arise from lateral branches of the intermediate hyphae; in P. verecunda they are capitate and carried upon short stems arising from the basal layer.
P. vesiculosa may be separated from the others by the coarsely crystal coated conical cystidia confined to the hymenial region, and pip-shaped spores. Fructifications are sometimes composed of several strata. Gloeocystidia are scanty and confined to the hymenial region, project and are often collapsed and difficult to detect. Spores frequently adhere in pairs or fours as in Corticium coprosmae.

Auckland: Kaiwaka, May, 1949, J.M. Dingley; type collection, P.D.D. herbarium, No. 7351

Basidiome annual, resupinate, effused. In section the structure is distinctly duplex, showing a loose white basal layer, a dense brown subhymenial layer and a cream-coloured hymenium. Hymenophore even, rarely warted, cracked, cream-coloured to ochraceous. Hyphae hyaline, thin- to somewhat thick-walled in the basal layer, 2-4(-4.5) µm, with distinct clamps. Vesicles stalked, in the basal layer up to 12 µm diam., in the upper layer up to 7(-8) µm diam., often with resinous contents. Clusters of crystals present in the trama, sometimes mimicking cystidia. Hymenial cystidia clavate, thin-walled, smooth or rarely finely encrusted, 30-50 x 5.5-6.5 µm, with hyaline or sometimes refractive material. Basidia narrowly clavate to nearly cylindrical, sometimes sinuous, 18-25 x 4-5 µm. Spores hyaline, thin-walled, smooth, ellipsoid to slightly flattened, 4.5-6(-6.5) x 2.5-3 x 3-4 µm, not amyloid.

The species belongs to Chondrostereum Pouzar because of the duplex structure, the vesicles, the hymenial structure and the narrow basidia. It is close to C. coprosmae (G.H. Cunn.) Stalpers, another species of this genus endemic to New Zealand.

Holotype: on Pittosporum eugenioides, New Zealand, Auckland, Kaiwaka, coll. J.M. Dingley, May 1949 (PDD 7351).