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 Add this item to the list  D. subcapitatus sp. nov.
   
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Page number:408 
Description type:Original description 
Description:D. subcapitatus sp. nov.
Fruit-bodies 0.5-1 mm. high, occasionally -4 mm. high, erumpent, rather densely gregarious, not caespitose, simple, white: stem 200-800 x 30-70 µm, occasionally to 3-5 mm. long, but equally slender, slightly enlarged at the inserted base, 40-130 µm wide, straight, cylindric, puberulous, pellucid white: fertile head 90-350 x 130-250 µm wide (excluding cystidia), globose to narrowly clavate, puberulous, opaque shining white.
On the underside of dead leaves of Eugenia cerina (Myrtaceae) : Malaya (Singapore, Botanic Gardens, 17.3.43, 27.3.43).
Spores 11-13 x 3-4(-4.5) µm, white, smooth, thin-walled, cylindric, blunt at the apex, shortly apiculate at the base, cloudy-vacuolate, aguttate.
Basidia 2o-28 x 6-7 µm, subclavate, hyaline: sterigmata 2, 5-7 µm long, occasionally only 1 sterigma 7-10 µm long.
Conical cystidia 30-75 x 9-15 µm, conical-ventricose, acute, the walls 1-4 µm thick, generally thickest in the distal half; the narrow tip often nearly solid, becoming slightly and finely rugulose, not incrusted, colourless, hyaline, projecting.
Lobed cystidia 18-35 x 5-9 µm, cylindric or subventricose, set with simple or lobed blunt processes -3.5 x 1.5 µm in the distal half or third, slightly thick-walled, generally slightly incrusted.
Hymenium not thickening, sometimes extended shortly down one side of the stem or lacking from one side of the head: subhymenium compact, distinct, with short uninflated cells 5-11 x 2-4 µm. Caulocystidia -70 x 4-7 µm, narrowly conical, acute, not incrusted, often very slightly rugulose, the walls 1-1.5 µm thick, scattered, generally absent from the base of the stem. Stem without sterile hymenium or a covering of hyphae.
Hyphae dimitic: skeletal hyphae 4-8 µm wide, the walls 0.5-3 µm thick, often nearly solid and glassy, aseptate, unbranched, of limited growth, traversing the stem longitudinally and ending in tapering, 1-3 µm wide, simple or 2-3-fid tips in the head, often dilated 6-12 µm wide at the base of the stem on origin from the generative hyphae: generative hyphae 2-4 µm wide, without clamps, cells -150 µm long, thin-walled, little branched in the stem, profusely branched and short-celled in the head.
This species combines the characters of D. laevis and D. capitatus. It resembles D. laevis in its spores, 2-spored basidia, caulocystidia (which are narrower), the tendency of the stem to elongate and of the hymenium to develop over the distal part of the stem, not merely at the apex, so that the hymenium is not discoid at first: its conical cystidia are also not deeply immersed. On the other hand, as in D. capitatus, the stem is generally short and limited to the length of one set of skeletals, the fertile part is also reduced, the conical cystidia are rugulose, and the lobed cystidia slightly incrusted.
In the occasional fruit-bodies of D. subcapitatus with elongate stem, the skeletals are more elongate, 1-z mm. long as in D. laevis, but those which end at the apex of the fruit-body have the characteristic lobed ends of D. subcapitatus. The elongated fruit-bodies have a small capitate or subclavate head of normal size and long sterile stem occasionally with discontinuous patches of hymenium on the sides.
The fruit-bodies of D. subcapitatus grow on the underside of the same leaf on which the fruit-bodies of D. laevis grow from the upperside. It is thus possible that they are two unexpectedly different states of the same fungus, D. laevis being negatively geotropic, long and of scattered habit, and D. subcapitatus positively geotropic, short and of rather crowded habit. I saw no intermediate states.
 
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