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

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THE BOLETES OF MICHIGAN

crassus, pallide luteus, tactu tarde caerulescens, insipidus. Tubuli circa 10
mm longi, pallide lutei demum laete lutei, tactu caerulescens. Stipes
4-12 cm longus, 1-2 (3) cm crassus, intus luteus, tactu caerulescens,
obscure reticulatus, extus luteus vel sursum roseus, saepe deorsum roseus
vel purpureus. Sporae 10-14 X 3.5-4.5 I. Cuticula pileorum hyphae
appressi, 3-5 (7), diam., tubulosi. Specimen typicum in Herb. Univ.
Mich. conservatum est; prope Tahquamenon Falls State Park, Luce
County, July 2, 1965, legit Smith 71688.
Pileus 4-10 cm broad, convex becoming broadly convex or nearly
plane; surface dry and unpolished, at times finely tomentose, with a
narrow sterile margin; color some shade of rose or brick-red, but soon
developing a grayish overtone from a very thin fibrillose coating, or in
slowly developing basidiocarps "warm sepia" to yellowish brown in
button stages. Context thick, pale yellow, slowly staining pale blue on
injury, odor and taste not distinctive, with FeSO4 bleaching the blue
areas to yellow again.
Tubes about 10 mm deep, when mature depressed around the
stipe, grayish yellow to yellow, finally bright yellow, staining blue when
injured; pores nearly round and 2-3 per mm, yellow when young,
often reddish near stipe in age in some specimens, staining blue where
injured.
Stipe 4-12 cm long, 1-2 (3) cm thick, equal, solid, yellow within,
finally red around larval tunnels, staining pale blue when cut; surface
very finely reticulate over upper half or nearly to the base, yellow overall at first but often with a red zone at the apex and often pinkish red
to purplish red below, later on the base usually yellow, not distinctly
rooting but sunken in the substratum at times.
Spore deposit olive-brown; spores 10-14 X 3.54.5 i, narrowly
ventricose (boat-shaped) in face view, in profile narrowly inequilateral,
smooth, wall slightly thickened, bright yellow in KOH, in Melzer's dull
yellowish or with a greenish gray shadow indicating a fleeting-amyloid
reaction.
Basidia 4-spored, short-clavate, 20-27 X 9-11 I, yellowish to hyaline in KOH and Melzer's (but blocks of tubes revived in Melzer's turn
bluish to greenish black). Pleurocystidia scattered, 36-52 X 9-13 I,
fusoid-ventricose, neck tapered to a more or less acute apex, walls thin,
smooth, content not distinctive in either KOH or Melzer's.
Tube trama of hyphae somewhat divergent from a central strand.
Cuticle of pileus an interwoven layer of hyphae 3-5 (7) I in diameter,
ochraceous in KOH and with orange brownish content in Melzer's, the
hyphae flexuous and intricately interwoven, smooth or at times with