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

LECCINUM

147

the margin, in age somewhat alutaceous with olive tones along the margin if wet. Context firm, hard, and white, soft in age, when cut staining
quickly to vinaceous then to violaceous-fuscous, with FeS04 blue-green,
with KOH no reaction in or on the stipe-base but on tubes pale cinnamon.
Tubes pallid to olivaceous yellowish and on maturing becoming
avellaneous to wood-brown, about 1.5 cm long, depressed around the
stipe; pores minute, olive whitish when young and soon staining yellowish if lightly bruised but sepia if severely bruised.
Stipe 8-10 cm long, 2-2.5 cm thick, solid, firm, hard, fibrous,
pithy in the center, when cut slowly changing to fuscous, surface white,
ornamented with fuscous-brown squamules and points, slowly staining
brownish around base from handling.
Spore deposit between cinnamon-brown and bister; spores 12.5-15
X 4-5 u, smooth, walls thickened slightly, subfusoid (with blunt ends in
face view), somewhat inequilateral in profile, suprahilar depression often
broad and distinct, dingy ochraceous in KOH, yellowish in Melzer's.
Basidia 4-spored, clavate, 8-9,u broad, hyaline in KOH and yellowish in Melzer's. Pleurocystidia 37-66 X 9-14 g, fusoid-ventricose, apices
obtuse, thin-walled, content pale cinnamon in KOH when fresh, darker
cinnamon when revived in KOH, near sepia in Melzer's. Cheilocystidia
24-33 X 6-10g, clavate to ventricose-rostrate or fusoid-ventricose,
ochraceous in KOH, soon gelatinizing. Caulocystidia varying from clavate
to fusoid-ventricose, the content sepia in fresh material, all smooth and
thin-walled.
Pileus epicutis of tangled hyphae (5) 7-12 (22) / in diameter,
many slender hyphae 5-10 L wide, tubular, with end-cells tapered slightly, walls thin and smooth to minutely roughened, content dingy ochraceous to orange-brown in KOH, content reddish brown and granular in
Melzer's; the broader hyphae (10-22 j wide) with short cells 15-60 p
long, their walls smooth or roughened and the walls parallel as seen in
optical sections, or only slightly bulging (not sphaerocyst-like), end-cells
often short and bullet-shaped; subcutis of hyaline hyphae in either KOH
of Melzer's, smooth, finally subgelatinous. Context of hyaline smooth
interwoven hyphae both in KOH and Melzer's. Clamp connections none.
Habit, habitat, and distribution.-In low woods of white birch and
aspen, Upper Peninsula, but most likely throughout the aspen-white
birch belt of the state, in early summer.
Observations.-The dull cinnamon-colored pileus distinguishes this
species from its close relatives, which show a reddish stain before the
color change to fuscous sets in.