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

BOLETUS

225

buttons with a lubricous feel when wet, otherwise dry and at maturity
coarsely rough tomentose to somewhat areolate or rimose-scaly, almost
granular-scaly in some, color dark dull red to brownish red to grayish
brown ("chocolate," "burnt-umber," "dark vinaceous-fawn," or duller).
Context thick, firm, pallid, or tinged vinaceous near the cuticle, unchanging when bruised, yellow when dried, odor and taste not distinctive.
Tubes depressed around the stipe, about 2 cm long, pallid at first
but very soon pale yellow and finally greenish yellow ("olive-ocher"),
when bruised staining mustard-yellow rather readily; pores round or
nearly so, about 1 mm in diameter, staining yellow when bruised.
Stipe 8-12 (20) cm long, 1-3.5 cm thick at apex, clavate, 3-7 cm
at base, solid, cortex sordid vinaceous near apex, inward vinaceous
especially around the larval tunnels, becoming yellow in drying; surface
dull sordid reddish to reddish brown, at times with a tinge of purple
(more or less concolorous with pileus), often reticulate near apex,
cuticle often splitting and becoming rough and unpolished, with a thin
pruinose coating at first, surface uneven to shallowly pitted at times, the
base usually becoming a darker reddish brown where handled.
Spore deposit olive-brown; spores 19-24 X 7-9 pg, smooth, shape in
profile somewhat inequilateral, in face view subventricose or varying to
narrowly elliptic, color pale ochraceous in KOH, revived in Melzer's
many spores clouded grayish and only a few clearly dextrinoid, lacking
an apical pore.
Basidia 4-spored, 36-42 X 10-12 u, hyaline in KOH, yellow in
Melzer's. Pleurocystidia 52-74 X 10-15 #, fusoid-ventricose with apex
obtuse, thin-walled, hyaline in KOH, fairly abundant.
Tube trama gelatinous, the hyphae divergent from a central floccose strand. Cuticle of pileus a turf of filamentose septate hyphae the
cells comparatively short (26-80 X 10-15 p), the pigment rapidly disintegrating in KOH, groups of hyphae pale yellowish, walls smooth in
KOH but with amorphous debris present in the fascicles. Clamp connections absent.
Habit, habitat, and distribution.-Solitary to subcespitose on decayed conifer logs, mostly on hemlock (Tsuga). It is rarely collected in
the Upper Peninsula (Luce County, Smith 38627) in regions where hemlock grows, but is common in the Pacific Northwest. It is an excellent
edible species.
Observations.-The large spores, colors, rough pileus, and habitat
on conifer logs make it a species anyone can learn to recognize accurately. The reticulation of the stipe apex may be quite coarse and conspicuous (P1. 88) or it may be absent. We have seen specimens with