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

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THE BOLETES OF MICHIGAN

yellowish tan when mature, staining slowly to avellaneous when bruised
severely, where bruised lightly staining olive.
Stipe 8-16 cm long, 1-2 cm thick at apex, evenly enlarged downward, slowly staining lilac-fuscous; surface with snuff-brown ornamentation finally becoming black, white ground color readily visible, base at
times with greenish blue stains.
Spores 13-16 X 4.5-5.5 (6) u, smooth, walls -0.5 y thick, apex
with a minute thin spot; color ochraceous in KOH to brownish ochraceous in Melzer's, many slightly more brownish; shape in face view
fusoid, in profile inequilateral.
Basidia 20-30 X 8-11 Ji, 4-spored, clavate, hyaline in KOH. Pleurocystidia scattered, 32-48 X 9-15 pi, fusoid-ventricose with neck elongated
and apex subacute, content hyaline to dingy brown in KOH, in Melzer's
darker reddish brown (but not dextrinoid). Cheilocystidia smaller than
pleurocystidia and neck typically shorter, more often with colored content than not. Caulocystidia mostly saccate to clavate and with a long
pedicel, 30-65 X 9-25 ji, content bister in KOH or Melzer's.
Tube trama typical of the section; some laticiferous elements present. Pileus cutis of appressed hyphae 5-9 (10-15) i wide, usually tubular and often with minutely ornamented walls in f. insigne, cells short or
long but mostly over 5 times as long as wide, cells disarticulating, endcells bullet-shaped to cystidioid, content dull orange-ochraceous to
brownish in KOH, not distinctively colored in Melzer's but aggregating
into beads 0.5-3,u in diameter and very rarely globules almost the diameter of the narrower cells. Hyphae of the subcutis to some extent at
least with orange-yellow content in Melzer's.
Habit, habitat, and distribution.-Scattered under mixed hardwoods including Populus, Fagus, Betula, Ostrya, and Corylus. Fruiting in
June, Emmet County.
Observations.-This is clearly a variant of L. insigne in which the
pileus is very dull in color, in which the stipe ornamentation is dull
yellow-brown at first, which not infrequently has spores up to 6 A wide
and pigment beads present in some of the cuticular hyphae when
mounted in Melzer's.
81e. Leccinum insigne f. lateritium
Pileus 4-12 cm broad, obtuse to convex, margin with a sterile
band breaking into segments as pileus expand, surface dry and fibrillose,
"auburn" to "Kaiser-brown" over disc, paler and more ochraceous near