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

300

THE BOLETES OF MICHIGAN

homogeneous and ochraceous in KOH, more orange-ochraceous in
Melzer's but remaining homogeneous. Context hyphae with some ochraceous-orange content but not truly distinctive. In mounts in Melzer's
scattered yellowish globules 2-4 in diameter occur throughout the
mount. No clamps observed.
Observations.-This species has been placed in synonymy with B.
rubinellus by some, but we are not prepared to accept this at present. B.
rubinellus has a subtomentose pileus which is red, has bright yellow flesh,
more strongly dextrinoid spores which are slightly longer than in Kauffman's species and possibly differs in the color of the stipe.
158. Boletus pseudorubinellus Smith & Thiers, sp. nov.
Pileus 1.5-5 cm latus, obtuse conicus vel convexus, glaber vel subsquamulosus, pallide luteus demum rufo-cinnamomeus vel testaceus.
Contextus pallide luteus. Tubuli rosei. Stipes 2-6 cm longus, 4-12 mm
crassus, intus luteus vel subroseus, extus pruinosus, roseus. Sporae 9-13
X 3-4 M. Pleurocystidia infrequentibus. Specimen typicum in Herb. Univ.
Mich. conservatum est; prope Burt Lake, legit Smith 77910.
Pileus 1.5-5 cm broad, obtusely conic to convex, expanding to
umbonate or broadly convex, glabrous to minutely appressed-squamulose, surface viscid to subviscid, when young "cream-buff' (yellowish),
slowly becoming pinkish cinnamon and finally testaceous, sometimes
squamulose, reddish on an ochraceous ground color. Context pale
yellow, unchanging when cut, FeSO4 no reaction, NH4OH on cuticle of
pileus no reaction, taste acid but not acrid.
Tubes 8-10 mm deep, bright rose-red overall including the pores;
depressed to decurrent; pores 1-2 mm wide, unchanging when bruised.
Stipe 2-6 cm long, 4-12 mm at apex, equal to clavate, solid,
yellow to pinkish within, unchanging when cut, surface finely pruinose
and more or less rose-pink except for yellowish region near base, base
with yellow mycelium over it.
Spores 9-13 X 3-4 J, smooth, no apical pore visible, in KOH distinctly olivaceous but on standing bright olive-yellow, in Melzer's dull
tan (as if shaded by a weak-amyloid reaction), in profile somewhat
inequilateral and narrow, in face view narrowly subfusoid, wall thin
(about 0.2 g).
Basidia 4-spored, 18-26 X 8-10 g, clavate, hyaline to yellow in
KOH, not distinctive in Melzer's. Pleurocystidia very rare and mostly
near pores, 32-45 X 7-12 g, hyaline, thin-walled, smooth, not distinctive
in Melzer's. Cheilocystidia rare to scattered, resembling pleurocystidia