Geniostoma ligustrifolium A.Cunn. Auckland: Te Araroa, 600ft, May 1952, G.H.C., type collection, P.D.D. herbarium, No. 11499. Leptospermum scoparium Forst. Auckland: Great King Island, Three Kings. 900ft, January 1952, E.E.Chamberlain; Moturoa Island, Bay of Islands, 100ft, May 1956, J.D.Atkinson.

Hymenophore resupinate, annual, membranous, fragile, adnate, appearing as irregular linear areas 2-10 x 1-2.5 cm. Hymenial surface dull umber, colliculose, deeply areolately creviced, tending to lift at margins of crevices; margin thinning out, concolorous, fibrillose, adnate. Context ferruginous, together with the hymenial layer 60-80 µ deep, consisting of a reddish-brown cemented zone lying upon the substratum and bearing scattered upright hyphae embedding masses of crystals; hyphal system monomitic; generative hyphae 2.5-3 µ diameter, walls 0.5 µ thick, branched, septate. Setal layer occupying the whole fructification, arranged in two rows, the upper arising from the subhymenium, the lower from the basal zone; setae projecting to 30 µ, subulate with acute apices, 35-55 x 6-8 µ, walls naked, reddish-brown, lumina narrow. Hymenial layer to 30 µ, deep, a close palisade of basidia and paraphyses. Basidia cucurbitiform, a few clavate, 12-16 x 4-4.5 µ, 2-4-spored; sterigmata arcuate, rather stout, to 4 µ long. Paraphyses subclavate, about half the length and the same diameter as the basidia. Spores oval or broadly elliptical, 6-7 x 3.5-4 µ, walls smooth, hyaline, 0.2 µ thick.

DISTRIBUTION: New Zealand.

HABITAT: Effused on bark of dead stems associated with a white rot.

Resupinata, annua, membranacea, fragilis, adnata. Superficies hymenii obscurate umbrina, colliculosa, rimosa; margine concolori, fibrilloso, adnato. Contextus ferrugineus, 2 ordinibus setarum hyphis erectis et multis crassis crystallis. Setae subulate, ad 30 µ eminentes, nudae, 35-55 x 6-8 µ. Basidia cucurbitiformis, aliquot clavata, 12-16 x 4-4.5 µ, 2-4 sporis ovalibus vel late ellipticas, 6-7 x 3.5-4 µ.

Separated from others of this section by the large oval or elliptical spores, small naked setae, narrow context and masses of embedded crystals. The hymenial surface is dingy umber and, as the margin is concolorous, colonies are difficult to see upon dead bark. Spores are broadly elliptical or oval, abundant, and possess one large gutta.
Crystals are so abundant as to appear in an almost continuous seam lying between the hymenial layer and the cemented basal zone. Between them lie a few upright hyphae which are sometimes difficult to detect.

Geniostoma ligustrifolium A.Cunn. Auckland: Te Araroa, 600ft, May 1952, G.H.C., type collection, P.D.D. herbarium, No. 11499.