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

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THE BOLETES OF MICHIGAN

severely injured staining avellaneous to fuscous readily, in age where not
injured with a dingy yellowish cinnamon tone.
Stipe 8-12 cm long, 1-2 cm thick near apex, evenly enlarged to
the base where it is 2.5-3 cm thick, often tapered to a point below,
solid, pallid when cut but soon darkening to fuscous on cut surface,
KOH usually yellow on the cut base; surface whitish and ornamented
with brown punctate dots or squamules which darken to blackish by
maturity or age, the surface underlying the ornamentation cottony and
uneven to obscurely reticulate, base dry.
Spore deposit dark yellow-brown ("snuff-brown" to "amberbrown"); spores 13-16 X 4-4.5 g, smooth, pale ochraceous in KOH,
lemon-yellow in Melzer's but a few becoming tawny, duller in both
KOH and Melzer's when revived, in profile somewhat inequilateral, in
face view subfusoid, wall slightly thickened.
Basidia 4-spored, clavate, hyaline in KOH. Pleurocystidia 42-56 X
10-15 J, fusoid-ventricose with subacute apex, thin-walled, hyaline in
KOH fresh, with dark brown content when revived in KOH. Cheilocystidia similar to pleurocystidia but neck often shorter and varying to
clavate not uncommonly, those in bruised areas with smoky ochraceous
content. Caulocystidia clavate to ventricose-mucronate, often resembling
pleurocystidia in size but giant cells 70 X 20 J also present and with
smoky brown content in KOH.
Pileus cutis of hyphae mostly 4-8 uI wide and end-cells tubular but
some hyphae 12-20 g wide, these most numerous on young pilei, with
either smooth or minutely roughened, hyphal cells of the large hyphae
short (often only 20-80 a long), and the end-cells frequently bulletshaped, hyphae of the cutis showing a tendency for the cells to disarticulate, content of cells ochraceous to brownish in KOH and in Melzer's
more ochraceous-orange cell content soon forming minute granules but
no large pigment globules in Melzer's. Hyphae of the subcutis in Melzer's
yellow to orange from colored homogeneous content. Hyphae of context hyaline in Melzer's. Clamp connections absent.
Habit, habitat, and distribution.-Common under large-toothed
aspen (Populus grandidentata) on low ground in June and early July or
throughout the summer if the weather is cool and wet. It may not be
limited to an association with large-toothed aspen. This is the common
early Leccinum with a red pileus and associated with aspen.
Observations.-This species, in the collective sense, has been mistaken for L. aurantiacum in North America in earlier times. We cannot
say as yet whether it occurs in northern Europe, but it is to be expected
there. It is a good edible species, though it is often difficult to find
specimens not infested with insect larvae.