The boletes of Michigan, by Alexander H. Smith and Harry D. Thiers.

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THE BOLETES OF MICHIGAN

Spores 8-11 X 3.5-4.5 a, smooth, apex lacking a pore; in face view
subelliptic, in profile suboblong to obscurely inequilateral, pale yellow in
KOH, slightly yellower in Melzer's, wall thin.
Basidia 4-spored, 8-12 p broad, yellow becoming hyaline in KOH.
Pleurocystidia abundant, 38-70 (100) X 9-16 p, fusoid-ventricose, smooth,
thin-walled, content yellow in water, in KOH yellow but soon dissolving
into the medium. Cheilocystidia similar to pleurocystidia or smaller.
Caulocystidia of elongate-clavate cells with curved pedicels, 36-70 X
9-10 u, thin-walled, soon hyaline in KOH mounts.
Tube trama of the Boletus subtype, yellow pigment diffusing out
when the tissue is revived in KOH. Pileus cutis a layer of matted-down,
tangled hyphae at maturity, the hyphae 6-12 (20) p wide and some of
the cells slightly inflated, cell content yellow in KOH but soon hyaline,
in Melzer's orange-ochraceous and many of the wide hyphae with conspicuous dextrinoid patches of material adhering variously, these less
evident in KOH because of being nearly hyaline, end-cells tubular to
somewhat cystidioid. Hyphae of subcutis and adjacent context orangeochraceous in Melzer's. Clamp connections absent.
Collected in the Waterloo Recreation Area, Washtenaw County,
August 13, 1968, by Mrs. Florence Hoseney 1081.
Observations.-The descriptive data included here are from Smith
10913 collected in the Great Smoky Mountains National Park in 1938.
The species is very rare in Michigan according to our experience. Mrs.
Hoseney's collection is the only one to come to our attention to date.
The stipe is moist at first but becomes sticky if handled very
much; it is not viscid from a gelatinous layer. The large cystidia, small
spores pale in color, and the brilliant yellow hymenophore are distinctive.
120. Boletus roxanae Frost
Bull. Buff. Soc. Nat. Sci. 2:104. 1874
Xerocomus roxanae (Frost) Snell, Mycologia 37:383. 1945.
Illus. Figs. 59-62; P1. 98.
Pileus 3-8 cm broad, obtuse to convex, becoming expandedumbonate to broadly convex; surface dry, granulose-roughened by
minute tufts of epicuticular elements but in age merely glabrous and
unpolished; color near ferruginous when young and fresh ("hazel"), but
soon more ochraceous toward the margin which is even and fertile;
surface when dried ochraceous to tan. Context firm, thick, buffy white,