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Text-Fig. 4. Plate 23, B.
Receptacula ad 3.5 cm. alta, solitaria, ravo-alba, ter vel quater divisa, primum trichotoma denique dichotoma, ramis levibus ravo-brunneolis: trunco distincto paulo brunneolo: apices inflati et impariter incrassati: sporae albae 3–5 × 2.5–4μ: basidia tetrasporifera, attenuata et clavata: hyphae fibulatae 2–6μ latae: ad terram nudam, Wellington, Novae Zealandeae.
Fruit body –3.5 cm. high, solitary, greyish-white: branched 3 to 4 times, at first trichotomously finally dichotomously; branches smooth, grey-brown, cylindrical; stalk distinct, tinged with brown; apices swollen and irregularly thickened, whitish-grey.
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Growing at the side of the track to Butterfly Creek, Eastbourne, Wellington, New Zealand (D. A. Crawford and J. H. Warcup No. 68, June, 1946).
Spores 3–5 × 2.5–4μ white, smooth walled, drop shaped, aguttate to once guttulate, apiculus terminal.
Basidia 3.4–5μ wide by –21μ long, clavate, slender, clamped at base; sterigmata (2-) 4, 4–5μ long with a slight outward curvature. Hymenium amphigenous, absent from stalk and lower parts of branches, –25μ wide. Colour in cytoplasm of hymenium layer.
The swollen apices in transverse section show a pseudoparenchymatous central medulla of longitudinal hyphae, surrounded by an inflated aerenchymatous region, traversed by strands of loosely interwoven hyphae, passing from the central medulla to an outer compact region underlying the irregularly convoluted hymenium, and filling the knob-like projections (see text-fig. IV). Apparently growth in the apical region becomes localized at a number of areas, giving rise at first to fairly regular rounded projections, but later with further outward growth these extend and become more irregular. A transverse section of a branch below
Text-Fig. IV.
Tumidapexus ravus.
A. Swollen apex × 3 ½. B. Transverse section through apical region. C. Transverse section through branch just below final division. D. Medullary hyphae showing different types of clamps and branching E. Spores. F. Portion of hymenium showing mature basidium and developing basidia. Magnification of B and C approx. × IS, D, E&F × 750.
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the swollen apex shows a central loose pseudoparenchymatous medulla surrounded by a uniform subhymenium and hymenium.
Hyphae monomitic, 2–6μ wide, not inflated, length variable, clamped; walls slightly thickened. Medullary hyphae elongated, a few interwoven; clamps often elongated, swollen or extended into a branch. In subhymenium hyphae narrower, shorter and interwoven, clamps normal.
The swollen apices with their irregular growth separate this species from other members of the Clavariaceae. However, hyphal and basidial structure is in line with the characteristics of the family as is the amphigenous hymenium, extending from the upper branches to the apices.