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

BOLETUS

275

Tube trama as revived in KOH of hyphae 5-11 p wide, the walls
thin and hyaline, not clearly divergent, inamyloid in all parts. Pileus
cuticle a trichodermium, its elements 2-5 cells long, the apical cell 20-50
X 10-18 p or at times becoming secondarily septate with the tip cell
subglobose and 8-10 p wide, apical cells generally cylindric, ovate, or
cystidioid with the apex obtuse, the wall roughened with thin plates of
wall material which are hyaline in KOH or in Melzer's, the remainder of
the cells similarly ornamented, content as revived in KOH yellow to
hyaline (soluble in KOH). Hyphae of subcutis and of adjacent context
not colored distinctively in Melzer's. Clamp connections absent.
Habit, habitat, and distribution.-Three basidiocarps gregarious
along a woods road on Colonial Point, Burt Lake, Cheboygan County,
July 24, 1968, were found, Smith 75673.
Observations.-The distinctive features of this species are the
flame-colored pileus at maturity-which then dries olive-buff-the
smooth spores, wide boletinoid pores, weak change to blue when injured, the thick stipe, and the very fragile context along with the details
of the trichodermial elements of the pileus. We did not note colored
(reddish) pores on the collection cited.
145. Boletus bicolor Peck
Ann. Rept. N. Y. State Mus. 24:78. 1872
var. bicolor
Suillus bicolor (Peck) Kuntze, Rev. Gen. PI. 3(2):535. 1898.
Ceriomyces bicolor (Peck) Murrill, Mycologia 1:152. 1909.
Boletus rubellus ssp bicolor (Peck) Singer, Amer. Midi. Nat. 37:53. 1947.
Illus. Figs. 70, 73-75; Pi. 109.
Pileus 5-15 cm broad, convex becoming plane to irregular; surface
dry, unpolished, under a lens appearing pruinose-granulose to occasionally glabrous at first, in age becoming subtomentose and areolate,
margin entire, with a narrow sterile band at maturity, deep apple-red
("Acajou-red" to "Pompeian-red," "old'rose," or "Vandyke-red") and
gradually becoming pinkish red in age, or toward the margin yellowish
("warm buff"), in age yellowish from exposed flesh but areolae remaining reddish. Context thick and firm (up to 1.5 cm), punky in age, pale
yellow, slowly turning blue when cut, odor none, taste mild.
Tubes about 1 cm long, when mature, adnate becoming shallowly
or sharply depressed around the stipe, yellow ("honey-yellow" to