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

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THE BOLETES OF MICHIGAN

125. Boletus illudens Peck
Ann. Rept. N. Y. State Mus. 50:108. 1897
Ceriomyces illudens (Peck) Murrill, North Amer. Fl. 9:145. 1910.
Xerocomus illudens (Peck) Singer, Farlowia 2:293. 1945.
Illus. Figs. 64, 66, 71; P1. 100.
Pileus 3-9 cm broad, convex to broadly convex expanding to
plane, rarely finally with a depressed disc; surface moist but not viscid,
unpolished to velvety but not becoming conspicuously areolate in age;
pale pinkish cinnamon to pinkish cinnamon, flushed lemon-yellow near
margin and drying with a strong yellow tone, margin even to irregular;
NH40H on surface Paris-green, slowly changing to fuscous, with KOH
dark brown. Context pallid when young, soon bright yellowish, unchanging when cut, odor and taste not distinctive; with guaiac no reaction,
with FeSO4 greenish gray going to olive-black.
Tubes adnate to subdecurrent, 1-1.5 cm long, honey-yellow to
olive-yellow; pores large and angular (1-2 mm wide or more in radial
direction), lemon-yellow and unchanging when bruised or only slightly
yellower but in age bruised portions often brownish; tubes splitting
rather than separating when pileus is broken downward.
Stipe 3-9 cm long, (4) 6-13 mm wide at apex, narrowed downward, mustard-yellow in the cortex and base, paler in the interior;
surface yellowish to mustard-yellow around the base, pallid to brownish
upward but pale lemon-yellow near apex, usually marked by coarse
ridges and anastomosing lines but not finely reticulate.
Spore deposit olive becoming olive-brown to buffy brown; spores
10-14 X 4-5 p, shape in face view subelliptic to subfusoid, in profile
somewhat inequilateral, surtace smooth, suprahilar depression often distinct, yellow in KOH, bluish gray slowly becoming brownish in Melzer's
(fleeting amyloid), rarely slightly dextrinoid, no apical pore evident.
Basidia 4-spored, 24-32 X 7-9 M. Pleurocystidia narrowly and.
obtusely fusoid, varying to narrowly fusoid-ventricose, 28-42 X 7-12 g,
thin-walled, hyaline to yellowish in KOH and in Melzer's, content
homogeneous as revived. Cheilocystidia smaller than pleurocystidia
(20-35 X 5-8 u), more frequently varying to clavate and with more
highly colored (brownish) content as revived.
Tube trama of subparallel hyphae only slightly divergent near the
subhymenium, in KOH in some mounts long, hyaline, needle-like crystals form, no crystals seen in mounts in Melzer's. Pileus trichodermium
of tangled hyphae 4-12 g wide, the cells often short and some inflated