(1) on Ackama rosaefolia, North Auckland, Omahuta Forest, 19.VI.1963, J. M. Dingley, PPD 21244 (DAOM 97062): (2-8) Auckland Prov.; (2) Hoheria populnea, Waiatarua, Waitakere Range, 8.V.1963, DA0M 93838; (3) Neopanax arboreum [Pseudopanax arboreus] , Pureora, 21.III.1963, DAOM 97056; (4-7) 0learia rani; (4) Titirangi, 27.11.1963, J. M. D., DAOM 97055; (5) Fairy Falls Track. Waitakere Range, 7.VIII.1963, J. M. D., PDD 21395 (DAOM 97059); (6) Waiatarua, 8.V.1963, DAOM 97045, (7) Waiatarua, 8.V.1963, PDD 30412 (type) (DAOM 97054); (8) on unidentified host, summit of Whitianga Rd, Coromandel Peninsula, 21.VIII.1963, J. M. D., DAOM 97057.

Capnokyma corticola is also present on periderm in a collection preserved in Herb. K, labelled -Antennaria. New Zealand [scr Berkeley]. Herb. Berk. 1879.

Colonies are black and extensive, forming a velutinous growth on trunks and branches of trees, often mixed with Acrogenotheca elegans. The mycelium is superficial although often found in the cracks of rough bark: it is composed of repent and erect aerial hyphae. The repent hyphae are cylindrical, smooth or faintly roughened, straight or variously bent, pale brown to brown, occasionally anastomosing, branched generally at right angles, septate, not constricted at the septa. Cells of repent hyphae are 25-40 um long and 7.2-12.6 um wide; the walls are 1.8-2.0 um wide and their double nature is conspicuous. At intervals, cells of the repent hyphae are darker, wider, and somewhat constricted at the septa; erect hyphae arise singly from one of these more robust cells and rooting hyphae appear to arise from the basal cell. The erect hyphae show considerable variation in size, form, and degree to which they are modified into conidiophores; nevertheless it is convenient to describe the sterile erect hyphae, those hyphae which are entirely conidiogenous, and finally some of the intermediate forms (Fig. 1).

Sterile erect hyphae are up to 1.3 mm long, straight or flexuous, smooth throughout, and stand out at right angles to the substratum. They are composed of a main stalk which is almost cylindrical for most of its length, 18-30 um wide near the base, then expanding gradually to 25-33 um wide and finally tapering subulately to an almost acute apex: they are dark brown to almost black at the base, becoming paler toward the apex which is pale brown. Basal cells are 32-40 um long and then progressively shorter and 12.5-21.5 um long toward the distal end. This main stalk bears, toward the apex and produced in the same plane, 1 to 5, mostly 2 or 3 paired subulate, distally pointed, pale brown to subhyaline, lateral branches, the upper ones successively shorter: these branches are upwardly curved and the more robust ones may bear secondary paired lateral branches. It is not uncommon for only a solitary branch to arise from one cell, but most erect hyphae bear at least one pair of opposite branches. The outer wall of all lateral branches is continuous with the inner wall of the main stalk which, during extension, has burst through the outer wall layer: at the base of lateral branches the torn remains of the outer wall of the main stalk appear as an irregular frill. Erect hyphae modified entirely into conidiophores are often darker throughout than sterile hyphae, almost cylindrical, up to 1.4 mm long, 20-27 um wide at the base. expanding gradually to 25-30 um wide about half way along their length and then tapering gradually to 12.5-18 um wide at the apex. Conidiophores may be unbranched structures bearing a terminal conidium, or they may also produce solitary or paired, lateral, cylindrical, upwardly curved branches which also bear a terminal conidium. Such cylindrical lateral branches can take the place of one or more of the subulate lateral branches of otherwise sterile erect hyphae. Also, sterile subulate paired or solitary branches may develop on otherwise simple conidiophores. The result is an almost infinite variety of branching structures, some of which are illustrated in Fig. 1.

Conidia arise blastically and their narrowed origin is indicated by a darker zone of wall on both apical cell of the conidiophore and basal cell of the conidium. At maturity, conidia are pale brown to brown, smooth, obclavate, slightly or markedly curved, (6-)8-10(-11)-septate, barely or only slightly constricted at the septa, (90-) 100-130(-150) um long and (20-)21-24(-27) um wide. Occasionally a conidiophore has proliferated through the terminal scar left by a seceded conidium and the extension has produced another terminal conidium. Any cell of a conidium can germinate and paired hyphae arising from a single cell have been seen.

Erect hyphae may bear a Horn i i.ycioniyces phialidic state, terminally on one or more lateral branches. The phialides are borne in a whorl of 6 or 7: they are pale brown, flask-shaped with the venters 4.5-5.5 um wide, each with a short neck, 2.0-2.2 um long, directed inwards toward the centre of the whorl. Phialoconidia are hyaline. broadly ellipsoidal, c. 2.5 X 1.5 um, and produced in a slimy head. Hormisciomyces phialides have been observed on simple and on branched hyphae arising from germinating Capnokyma conidia.