Coprosma australis (A. Rich.) Robinson. Auckland: Off Anawhata Road, Waitakeres, 1,000ft., June, 1946, J.M. Dingley, type collection, P.D.D. herbarium, No. 4525; same locality, April, 1947, M. Ambler; Cutty Grass Road, Waitakeres, 1,000ft., April, 1949, J. M. Dingley; Upper Piha Valley, August, 1949, J.M. Dingley; Mt. Atkinson, Titirangi, 1,000ft., May, 1950, J.M. Dingley; Mountain Road, Henderson, 600ft., July, 1950, J.M. Dingley. Coprosma robusta Raoul. Auckland: Mt. Te Aroha. 1,100ft., December, 1953. G.H.C. Wellington: Lake Papaetonga, 50ft., September, 1953, G.H.C.

Hymenophore annual, tending to lift at edges of crevices and curl at margins when old, ceraceous, effused forming linear areas to 18 x 5 cm., with several orbicular outlying islands; surface cream, becoming fawn or tan, even, at length creviced; margin thinning out, white, arachnoid, adnate but tending to lift when old. Context white, 150-250 µ thick, composed of a compact basal layer of parallel hyphae and an intermediate layer of loosely arranged upright hyphae somewhat corymbose beneath the hymenium, crystal coated or naked; generative hyphae 4-5 µ diameter commonly 3-4 µ, wall 0.5 µ thick, hyaline, somewhat oval in section, branched, septate, with clamp connections. Hymenial layer 50-60 µ deep, of basidia, paraphyses and gloeocystidia. Basidia subclavate or as often subcylindrical, 12-20 x 3-5 µ, 4-spored; sterigmata slender, to 4 µ long. Paraphyses cylindrical or subclavate, narrower than the basidia. Gloeocystidia confined to the hymenial region, elongate-fusiforin, ventricose, some flexuous-cylindrical, attenuate to the apex, or inflated in the middle and tapering to ends, 30-64 x 6-8 µ, projecting to 25 µ, or not, base rounded, sometimes inflated to 12 µ, wall 0.5-1 µ thick; vesicles pyriform or subglobose, to 16 µ diameter, wall 11 µ thick, attached by a narrow neck, scattered in the intermediate layer, collapsing. Spores pip-shaped, with rounded apex and attenuate base, 5-6 x 2.5-3 µ, wall smooth, hyaline, 0.25 µ thick, sometimes adhering in fours.

DISTRIBUTION. New Zealand.

HABITAT. Effused on bark of dead branches.

Hymenophorum ceraceum, adnatum, effusum; superficie cremea deinde alutacea, aequa, demum rimosa. Hyphae contextu fibulatae, 4-5 µ diam., prope basim crystallis. Basidia 12-20 x 3-5 µ, 4 sporis. Gloeocystidia fusiformia vel ventricosa, 30-64 x 6-8 µ; vesiculis pyriformibus vel subglobosis, ad 16 µ diam. Sporae obovatae, attenuato-apiculatae, quaternae conglutinatae, 5-6 x 2.5-3 µ, laeves, hyalinae.

Gloeocystidia vary in shape and size, and are usually confined to the upper part of the context; they are often sparse and difficult to demonstrate save near growing margins. Associated vesicles are usually pyriform and attached by a narrow base, less often subglobose. Usually scattered through the context, sometimes arranged in a dense zone beneath the hymenial layer, vesicles may sometimes be seen only near margins. In mature specimens they usually disappear leaving cavities in the compact often pseudoparenchymatous tissues. Clamp connections are large and abundant in context hyphae, though absent from bases of gloeocystidia and vesicles. The fungus is probably a parasite, since collections have been taken from recently dead branches attached to living plants and still retaining some discoloured leaves.
Superficially the species resembles C. evolvens Fr. but differs in such microfeatures as much smaller spores and basidia, different gloeocystidia and presence of vesicles. It also resembles C. evolvens and C. gloeosporum Talbot in that the pip-shaped spores often adhere in fours.

Auckland: Off Anawhata Road, Waitakeres, 1,000ft., June, 1946, J.M. Dingley, type collection, P.D.D. herbarium, No. 4525