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

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THE BOLETES OF MICHIGAN

sordide lutei, immutabiles; pori lati (1-3 mm), laete lutei tactu leviter
aurantio-cinnamomei. Stipes 3-9 cm longus, 1-3 cm crassus, reticulatus,
subroseus, sursum demum subluteus, adbasin tenax. Sporae
9-12 X 4.5-5.5 (6) M. Specimen typicum in Herb. Univ. Mich. conservatum est; prope Ypsilanti, Washtenaw County, September 11, 1965,
legit Smith 72556.
Pileus 4-10 cm broad, convex with an incurved to inrolled margin,
becoming plane to shallowly depressed, margin at times uplifted and
irregular to lobed; surface plushlike, even at first but surface developing
depressions (as the flesh softens); color when young with an olive sheen
("buffy brown") overall, with a dull brick-red ground color, in age
"Pompeian-red" to "madder-brown" (almost rose-russet), margin obtuse
and even in age. Context soon soft, pallid, with a watery line next to
the tubes, bright pale yellow as dried, becoming vinaceous-brown around
the larval tunnels when fresh, taste acid, odor not distinctive, with
NH4OH on cuticle green then blue, finally fuscous; with KOH fuscous;
cut surface slowly flushing vinaceous (in 15 minutes); KOH and FeSO4
neither giving an appreciable reaction.
Tubes up to 12 mm deep, long-decurrent by lines, dull yellow
with a faint reflection when young, soon bright yellow, not staining blue
when injured, splitting if pileus is broken downward, not readily separable from the context; pores broad (1-3 mm radially or near stipe more
elongated), isodiametric near pileus margin, bright yellow becoming
dingy yellow in age, when bruised turning slightly reddish cinnamon to
orange (in age).
Stipe 3-9 cm long, 1-3 cm thick at apex, narrowed to 8-12 mm at
base, solid, pallid within, near base the cortex often tinged vinaceous,
basal area covered by yellowish to pallid mycelium; surface reticulate
overall or only over the upper half with a distinct wide-meshed fine
reticulum, dingy rose to pinkish cinnamon over most of its length but
becoming decidedly yellow in age or on drying, consistency very hard in
the lower part and the base tenaciously attached to the substratum by
binding mycelium.
Spores 9-12 X 4.5-5.5 (6) u, smooth, no apical pore apparent, in
profile somewhat inequilateral, in face view subfusoid to ovate, yellow
in KOH, in Melzer's amyloid when fresh, very weakly so as revived, wall
relatively thin.
Basidia 4-spored, 24-30 X 7-10 a, clavate, hyaline in KOH, merely
yellowish in Melzer's. Pleurocystidia scattered, 38-60 X 7-11 ju, narrowly
clavate to cylindric with subacute apex to narrowly fusoid, thin-walled,