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

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Stipe 2-6 cm long, 1-3 cm thick, equal or nearly so, solid, white
within staining avellaneous where cut; surface pallid above, about concolorous with the pileus below or a grayer brown, staining dull cinnamon overall in age, finely reticulate over the upper half.
Spore deposit "Verona-brown" (dingy vinaceous-cinnamon), slightly yellower as moisture escapes; spores 9-12 X 4.5-5,, subelliptic to
subventricose in face view, slightly inequilateral in profile and with a
distinct suprahilar depression, wall thickened (about 1 i) as measured in
KOH, in Melzer's pale tan to darker, in KOH ochraceous-hyaline singly
or cinnamon-buff in groups.
Basidia 18-23 X 7-9 x, 4-spored, short-clavate, hyaline in KOH.
Pleurocystidia scattered, 30-48 X 9-16 pi, ventricose in lower half, neck
long and tapered to a subacute apex or scarcely any neck present,
hyaline in KOH or some with an amorphous bister pigment inside, thinwalled, smooth, in Melzer's many with a reddish brown (dextrinoid)
amorphous internal wrinkled mass.
Hymenium in Melzer's with numerous dark violet granules variously dispersed in some collections. Tube trama of divergent hyphae from a
central strand, very gelatinous. Pileus cuticle a trichodermium, the
hyphae 4-5 pi wide, gelatinous, having few cross walls and a brown pigment diffusing out in KOH mounts, the layer'very soon collapsing, dark
reddish in Melzer's from the colored cell content, orange-brown pigment
globules numerous in the mount (as in many species of Rhizopogon).
Clamp connections none.
Habit, habitat, and distribution.-Scattered in grassy oak woods,
early fall, abundant after late summer rains in southeastern Michigan on
heavy clay soil which is packed rather hard.
Observations.-Singer's (1947) disposition of B. subpunctipes, B.
ferrugineus, and B. indecisus is not to be relied on. He stated of the
type of B. subpunctipes: "... obviously a specimen of T. ferrugineus
with entirely non-reticulated stipe." Peck described his species as having
a slight reticulation at the top, and he was in a more favorable position
than Singer to make the observation. Of T. ferrugineus Singer states the
flesh changes to pink and then brown, whereas Frost who described the
species described the flesh as unchangeable. Because of the confusion in
this group we do not care to sponsor a "new" species in it at present. In
the Michigan material the stipe, in addition to the reticulation, may be
more or less pruinose to pruinose-furfuraceous at first, which is not too
different from the condition Peck described. Also Peck indicated some
color change in the context. Consequently, we place our collections here
pending more accurate studies of the New England flora.