CONIFERAE. Pinus radiata: Nelson, Appleby, 30 m. CORIARIACEAE. Coriaria arborea: Auckland, Te Puna, coast. MYRTACEAE. Leptospermum ericoides: Auckland, Te Moehau, Coromandel Peninsula, 250 m. Wellington, Oturere River, Mt. Tongariro, 1,200 m. Leptospermum scoparium: Auckland, Mt. Te Aroha, 400 m, type collection, P.D.D. herbarium, No. 15238; Monument, Huia, 70 m. Wellington, Kaimanawa Ranges, 800-1,200 m.

Hymenophore annual, adherent, ceraceous-cretaceous, at first appearing as small linear scattered colonies 2-5 x 1-2 cm, becoming coalesced forming linear effused areas to 5 cm long; hymenial surface white, remaining so or becoming cream, or occasionally sulphur-yellow, at length deeply areolately creviced; margin thinning out, fibrillose, white, adherent. Context white, 120-160 µ thick, basal layer narrow, of mainly parallel hyphae, intermediate layer occupying the greater part of the context, of closely arranged erect hyphae soon cemented by their walls to form a pseudoparenchyma, embedding masses of crystals; generative hyphae forming the bulk of the hymenial layer, clavate or fusiform, to 6 µ, diameter, with the apical region covered with several (5-14) blunt processes 2-3 µ long. Gloeocystidia arising in the base of the context and subhymenium, some projecting slightly, fusiform or flexuous-cylindrical, 45-80 x 8-10 µ, apices rounded. Hymenial layer to 50 µ deep, a loose palisade of basidia, paraphyses, acanthophyses, and gloeocystidia. Basidia subclavate, 16-25 x 5-6 µ, bearing 4 spores; sterigmata slender, erect, to 6 µ long. Paraphyses subclavate, scanty, 12-18 x 4-5 µ. Spores elliptic-oblong with rounded ends, apiculate, 7-9 x 4-5 µ, walls smooth, hyaline, 0.2 µ thick, amyloid, often adhering in fours.

DISTRIBUTION: New Zealand.

HABITAT: Effused on bark of dead stems and branches.

Separated from other species bearing clavate acanthophyses by the small basidia, smooth elliptic oblong spores, and absence of clamp connections. The species resembles `Aleurodiscus' cerussatus (Bres.) H. & L. in surface features, presence of gloeocystidia, apically spined acanthophyses and smooth elliptical spores. It differs in that basidia are smaller, clamp connections absent, and spores are smaller and of different shape. In most collections the hymenial surface is white and remains so or changes to cream on drying; the collection from Coriaria arborea is rich cream with sulphur yellow areas where growing in bark crevices.

TYPE LOCALITY: Mt. Te Aroha, Auckland, New Zealand.