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Page number:117 
Remarks (internal):Gloeocystidiellum lactescens is associated with a white rot (Gilbertson & al. 1974) of logs and slash of angiosperms throughout North. America (Burt 1926; Freeman 1978). This species was isolated from test stakes and reported as Unknown F (Duncan & Lombard 1965). Table 6 compares G. lactescens with other species of Gloeocystidiellum. The cultures of G. lactescens described by Boidin (1958a) and Stalpers (1978) differ from those examined by Freeman (1978) and myself. Boidin and Stalpers observed arthroconidia in culture that were not present in the isolates Freeman and I studied. In addition, gloeocystidia, which are numerous and diagnostic in the isolates held at CFMR, were not observed by Boidin and Stalpers. It is quite possible that two different taxa are being called G. lactescens. I Gloeocystidiellum lactescens has been placed in Megalocystidium by Jülich (1978, p. 140) and in Vesiculomyces by Boidin a Lanquetin (1983, p. 493); also see discussion under G. porosum.  
Description type:Culture description 
Mats white, thin to moderately thick, some isolates appressed, silky but thinner toward margins, other isolates around inocula appressed and silky, then becoming raised and downy toward margins at 2 wk, by 6 wk white, some isolates thin, appressed, silky to subfelty throughout, other isolates moderately thick, slightly raised, subtomentose to downy and occasionally developing scattered Pinkish Buff to Light Pinkish Cinnamon, circular, raised, felty patches: margins uneven to bayed, appressed, fimbriate; no odor at 2 and 6 wk; agar unchanged at 2 wk, unchanged, partially or occasionally stained Warm Buff at 6 wk; not fruiting by 6 wk.
MEA 23-36; 43-65(-75); TAA ++++, (tr-)13-25; (18-)25-47; GAA ++++, 0-tr ; TyA - or yellow,tr-29; yellow,29-52
Microscopic characters: Marginal hyphae 1.5-4 µm diam, thin walled, simple septate, sparsely branched, usually branches arising below septa. Submerged and surface hyphae 1-5 ?m diam, thin walled, simple septate, narrower hyphae frequently branched but wider hyphae moderately branched. Aerial hyphae 0.5-2 µm diam, thin walled, simple septate, sparsely branched, with abundant encrustations of thin, elongated, hexagonal crystals (Fig. 32c). Gloeocystidia (Figs. 32a and 32b) variously shaped but mostly cylindrical, 30-100 x 2- 10 µm, thin walled, terminal or lateral, often branched or lobed, filled with light yellow, refractive, oil-like materials or globules, staining or not in phloxine, sometimes rather inconspicuous but numerous in aerial, surface, and submerged mats at 2 and 6 wk.
Sexuality: Heterothallic (Boidin 1958a, p. 108).
Cultural descriptions: Boidin (1958a, p. 108); Freeman (1978, p. 62); Stalpers (1978, p. 200).
Species code: 2. 6. 15. 32. 36. 38. (39). (40). 45-47.54.58.
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