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

BOLETUS

247

pileus as dried, differently shaped cells in the hyphae of the pileus
cuticle, and in having spores averaging slightly over 15 j long.
128. Boletus brunneocitrinus Smith & Thiers, sp. nov.
Pileus 3.5-5 cm latus, late convexus, siccus, subtomentosus, badius
demum olivaceus. Contextus luteus, immutabilis. Tubuli 15 mm longi,
sordide lutei; pori 1-2 per mm, sordide lutei, immutabiles. Stipes 5-8 cm
longus, 5-8 mm crassus, deorsum laete luteo-myceliosus, sursum pruinosus; pruina sordide luteobrunnea; nonreticulatus. Sporae 10-14 X 3.5 -4.5 (5) p. Specimen typicum in Herb. Univ. Mich. conservatum est;
prope Douglas Lake, Cheboygan County, July 1, 1968, legit Smith
75435.
Pileus 3.5-5 cm broad, broadly convex and remaining so, margin at
first incurved but not sterile; surface subtomentose to unpolished, continuous, dull reddish brown when wet, olivaceous after moisture has
escaped ("Vandyke-brown" wet, "dark olive-buff" to "citrine-drab" on
loss of moisture). Context yellow, not staining blue, pale buff as dried,
odor and taste not distinctive, NH4OH on pileus dull brown immediately.
Tubes ventricose and deeply depressed around the stipe (up to 15
mm deep), dull yellow and unchanging; pores at maturity 1-2 per mm,
angular to round, dull yellow, not staining blue.
Stipe 5-8 cm long, 5-8 mm thick, slender, solid, equal, yellowish
within becoming pallid, no color change when cut; base covered with
bright yellow mycelium, pruinose above the. lower third with bister
pruina on a yellowish to brownish ground color, not at all reticulate.
Spores 10-14 X 3.5-4.5 (5),, smooth, apex lacking a pore, shape
in face view subfusoid, in profile more or less inequilateral, color in
KOH pale bright yellow, in Melzer's yellow with a greenish gray shadow
(fleeting-amyloid reaction strong).
Basidia 4-spored, 24-35 X 8-11,u, yellow to hyaline in KOH or
Melzer's. Pleurocystidia 35-52 X 8-14,, fusoid-ventricose with obtuse to
subacute apex, thin-walled, hyaline or yellow in KOH but fading if
yellow at first. Cheilocystidia similar but smaller. Caulocystidia
28-42 X 9-13 ji, subcylindric to clavate, thin-walled, smooth, hyaline to
yellow in KOH, more rarely fusoid-ventricose.
Tube trama of the Xerocomus subtype, the hyphae hyaline inKOH,
5-9 u broad, walls not obviously gelatinous, fleeting-amyloid reaction
strong (sections violet-black in Melzer's but pigment not localized).
Pileus cuticle a trichodermium of wide (9-15 u) hyphae of globose to