Microscopic:
spores 14-16.5 x 7-8.3 microns, "finely granular-opalescent"; basidia (2-)4-spored, 38-50 x 15-17 microns; hyphae up to 10 microns wide, "very long-celled, without clamps, the walls firm, not agglutinated in the medulla"; "caulocystidia none, but the excrescent hyphae at the base of the stem - 1.5 mm long, 3-5 microns wide, with pale yellow brown walls 1-2 microns thick, aseptate, unbranched, smooth, with obtuse ends, not or scarcely tapered"; sclerotium structure as in T. phacorrhiza but cuticle thin (about 1 micron), and the outer layer of cells thin-walled, (Corner), spores similar to those of T. phacorrhiza but larger, 17-18 x 7.75-8.25 microns compared with 14-16 x 4.5-5.5 for T. phacorrhiza; inamyloid; basidia 4-spored; hyphae clamped, stem of a different structure than T. phacorrhiza "ecorce importante constituee, en bordure de 2-3 couches d''hyphes a paroi un peu epaisse, peut-etre unies par une mince gelee, et plus a l''interieur d''hyphes souvent plus grosses peut-etre unies par une gelee; moelle non lacuneuse faite d''hyphes (x 3-8 microns) a paroi mince"; "sclerote gelifie a epidermoide normal superficiel qui differe de celui de T. phacorrhiza par sa cuticule tres epaisse (6 microns) et ornee de stries anticlines: hyphe constitutives, de 4-5-7 microns de diametre, a paroi tres epaisse, partiellement gelifiee, unies par une gelee interstitielle" [accents omitted], hairs absent the length of the stem, but a crown of long "trichoides" at the base, comprised of simple hairs of regular diameter (2.5-3 microns), isolated or fasciculate [in bundles], with somewhat thickened walls and sometimes weakly colored, (Berthier)